Tribunal Criminal Tribunal for the Former Yugoslavia

Page 19941

1 Friday, 2 May 2003

2 [Open session]

3 [The accused entered court]

4 --- Upon commencing at 10.22 a.m.

5 JUDGE MAY: We are starting late, I'm afraid, because the case we

6 were hearing overran from yesterday afternoon and we had to finish it.

7 The upshot is that time is foreshortened, but we think that the most

8 expeditious way we can use it, having regard to the time which is

9 available and having regard to the requirement of all sides for time this

10 afternoon, is this: We will sit for an hour and a half now; we will

11 adjourn for half an hour; and we will then sit until 2.00 p.m.

12 Yes, Mr. Nice.

13 MR. NICE: The application is that we may interpose Mr. Ball to

14 deal with the corrigendum to his report, which was part of the Kosovo

15 evidence. The possibility of interposition was raised yesterday when Mr.

16 Ball's personal problems were identified. Those problems are that he has

17 a flight back to America booked for tomorrow and has commitments in

18 Chicago and California, I think, for next week to fit in with family

19 commitments and will not be able to meet those commitments if he doesn't

20 travel tomorrow.

21 JUDGE MAY: And --

22 MR. NICE: We notified the amicus and the accused via his

23 associate yesterday, and neither of them raised an objection at that

24 stage. I left a message with your legal officer. I believe the telephone

25 system here has had some problems, so the message may not have been

Page 19942

1 received immediately.

2 JUDGE MAY: He has come from the United States, flown across the

3 Atlantic to give evidence; is that right?

4 MR. NICE: He's certainly come from -- whether he's come direct, I

5 don't know. He travels all around the world. But the next limb is back

6 home for a day and then to Chicago and California.

7 JUDGE MAY: And how long do you anticipate being with him in

8 chief?

9 MR. NICE: Ten to fifteen minutes, I should think.

10 [Trial Chamber confers]

11 JUDGE MAY: Very well. We will interpose Dr. Ball for a short

12 period, and then we will return to the evidence which we were hearing.

13 MR. NICE: Before the witness comes to court, may I do something

14 I've done certainly once before, on I think the 22nd of April last year

15 and possibly since then. It relates to the possibility of using the

16 provisions of 92 bis in whole or part for all future witnesses in the

17 case. It was done certainly in April 2002 in respect of the Kosovo part

18 of the proceedings, but really I think expressly for all witnesses, and

19 the Chamber will recall that the provisions of 92 bis have been used in

20 part during some of the Croatia segment witnesses.

21 So at this stage I give notice under 92 bis (E) that we may seek

22 to rely on the provisions of 92 bis for every forthcoming witness insofar

23 as it is appropriate to do so. We will seek whatever relevant shortening

24 of time periods may be appropriate if we find that within the next 14 days

25 there are witnesses who we wish to give under the provisions in whole or

Page 19943

1 part of 92 bis for their evidence in chief.

2 But this notification relates to witness whom -- witnesses whom we

3 accept should properly be cross-examined. The position of witnesses who

4 we will be applying should be taken under 92 bis without cross-examination

5 will be the subject of the usual full written applications.

6 The Chamber may recall that on earlier occasions, having given a

7 general notice and working on the basis that there may be opposition of

8 the kind forecast under 92 bis (E) by the accused, the Chamber has then

9 dealt on a case-by-case basis with witnesses being provided by us with

10 either the statements in paragraph numbers or by the statements and

11 summaries so as to identify what parts of the evidence it is we seek to

12 give by 92 bis and what part we seek to give live. The timetable problems

13 on us are such that it is absolutely essential we optimise the use of

14 time, and it seems to us that the time has come when we simply must use 92

15 bis wherever possible, and we have in mind the Chamber's recent ruling on

16 the possible use of witness statements as evidence in chief where the

17 Chamber reminded us of the potential to use 92 bis.

18 The first witness who might qualify for this procedure is indeed

19 the next witness. Now, we may start him today, in which case he'll be

20 started live and that will be that. But if we don't reach him today, Mr.

21 Gusic is a witness who might be susceptible to 92 bis but we haven't yet

22 prepared his materials in a way that would identify precisely which parts

23 we would suggest would be acceptable under 92 bis and which parts, for

24 example, should be given live. It may be that there would be written

25 notification of our position on that by the end of the day; alternatively,

Page 19944

1 first thing on Monday morning, if -- if we don't start him.

2 JUDGE MAY: Yes.

3 MR. KAY: Can I deal with one matter? Because there's a danger

4 when you wrap everything up in that way that injustice can be caused,

5 because 14 days' notice is required with a particular witness, whether 92

6 bis provisions are to be applied, and for our part, we need to consider

7 whether the rule should properly apply or not, which takes a degree of

8 research and time to consider the matter.

9 JUDGE MAY: We'll not consider it in a vacuum. Let us receive an

10 application and then we can start dealing with it.

11 MR. KAY: I'm much obliged.

12 MR. NICE: And Your Honour, I think I've already said that I'm

13 going to be improving and regularly updating the witness list that has

14 been attached to the latest -- to the only application for time that we've

15 made, and that falls for determination in due course. In the newer

16 versions of that list - perhaps there will be one as soon as next week -

17 we'll have a column which I hope will identify prospectively what

18 witnesses may and what witnesses may not be susceptible to 92 bis in part.

19 So I think that will also be helpful.

20 Can I respectfully request from the Chamber a ruling in respect of

21 one witness whose name appears on the latest running list of witnesses, in

22 respect of whom we've sought leave that he be called for whom no decision

23 has yet been made. You'll see the name, and I've got the list. I can

24 tell you which one it is without reading it out publicly. It's -- it's on

25 the second page, and it's the second name on the second page.

Page 19945

1 [Trial Chamber and legal officer confer]

2 MR. NICE: Second page, second name.

3 JUDGE MAY: We think the matter is in hand, but that can be

4 checked.

5 Yes, Mr. Kay.

6 MR. KAY: There's one matter of concern about that witness, as I

7 can see from the table, and the Court will appreciate. This is a big

8 witness indeed, and --

9 JUDGE MAY: What's the matter of concern?

10 MR. KAY: We've received no statement or materials, of course, at

11 this stage in relation to that witness. There's a date for his testimony

12 which is apparently fixed as only being one particular date on which he is

13 available. Looking at the timetable of disclosure, adequate time for

14 preparation by the accused in relation to such a witness, I can register

15 concerns about a witness suddenly coming into the proceedings in that way

16 without adequate disclosure. The trial --

17 [Trial Chamber confers]

18 JUDGE MAY: Let us deal with it on this basis. At the moment -

19 again, it's purely hypothetical - we've merely got this list. There will

20 be an issue, of course, as to disclosure -- well, there may be an issue.

21 We'll have to see what happens when the Prosecution propose to call the

22 witness.

23 MR. KAY: Adequate time is a very important consideration.

24 JUDGE MAY: Mr. Nice, you have that point. Seeing the witness and

25 seeing who it is, that obviously must be right.

Page 19946

1 MR. NICE: Yes. But he's only being called on a very narrow

2 basis, a limited amount of material. I think five pages of notes will be

3 served and can probably be served pretty well immediately. And we are

4 certainly going to ask where we take any witness on a particularly narrow

5 basis, as we would take this witness in the short period of time, that

6 that doesn't open up the floodgates for endless cross-examination, because

7 to do so imperils our ability to prove the case within the time limits

8 that, whether amended or not, are imposed on us.

9 And of course, it's always -- take this particular witness,

10 without naming him. If, for example, we call him on a particularly narrow

11 issue for an hour's evidence or less and he's cross-examined and dealt

12 with on that, there's nothing to stop the accused calling the same

13 witness, if there's a whole lot more he wants, in his own case and in his

14 own time. And with witnesses who are capable of covering such a wide --

15 capable of covering such a wide part of the history, that may actually

16 sometimes be an appropriate course. We desire him only for limited

17 purposes and we will call him in a short period of time.

18 JUDGE MAY: Well, I notice the day is some way off that you

19 propose to call him. Has the statement been disclosed yet?

20 MR. NICE: No. We've been waiting for a determination on whether

21 he can be added to the list. But it can be done forthwith. It's not a

22 statement, it's actually notes, but it's the same as.

23 JUDGE MAY: We must resolve this. It's been granted, I'm told.

24 MR. NICE: Thank you very much.

25 JUDGE MAY: The decision is still being filed.

Page 19947

1 MR. NICE: Thank you. We'll disclose today.

2 JUDGE MAY: Very well.

3 MR. NICE: Thank you very much.

4 May the witness come in. The Chamber will probably want to be

5 able to refer to the report that the witness produced on the last

6 occasion, together with the submission of the corrigendum. I do not

7 intend to revisit the nature of his testimony in any detail but must take

8 it as -- as it were, read and recalled.

9 [The witness entered court]

10 MR. NICE: But it may be the Chamber, after this interval of time,

11 will or not want the witness to be re-sworn. I don't know.

12 JUDGE MAY: He needn't be re-sworn.

13 Dr. Ball, you -- Dr. Ball, you are, of course, under the

14 declaration which you made on the last occasion.

15 THE WITNESS: Yes, sir.

16 WITNESS: PATRICK BALL [Recalled]

17 Examined by Mr. Nice:

18 Q. Dr. Ball, you've produced a corrigendum which has text covering

19 just one and a half sides, and you then produced on pages 3 to 13 various

20 figures, charts, and graphs which are reruns, under different technical

21 procedures slightly, of graphs produced on the pages cited and referred to

22 in the earlier report. So that on page 3 of the addendum, to find that

23 graph, we have to go to page 2 -- figure 2 on page 6 of the original

24 report; is that correct?

25 A. That's correct.

Page 19948

1 Q. In fact, I'm only going to ask you probably to look at about two

2 figures. Before doing that, your corrigendum arises from the following:

3 First, did you find available to you, after giving evidence, further

4 material from open sources and from other material published in Belgrade

5 and elsewhere maybe, about NATO airstrikes occurring through early May and

6 early June of 1999?

7 A. Yes.

8 Q. Although your conclusions material to this case really related to

9 an earlier period, did you think it appropriate to add this later NATO

10 airstrike material?

11 A. Yes, we did.

12 Q. Does it have an effect on one of the figures that we can look at?

13 For example, figure 11, page 14, shown on page 9 of the addendum and of

14 course on page 14 of the original report.

15 A. Yes. You can see very small effects there.

16 Q. Which is the -- which is the chart that gives a better

17 demonstration of the effects?

18 A. Figure 19 has, I think, the clearest expression of those effects.

19 It's page 11 of the addendum.

20 Q. But I want to stay with the graph first.

21 A. All right.

22 Q. Because your expertise is only ever going to be understood by

23 laymen in a different way from the way you would understand it, and I want

24 to demonstrate something through this chart, which could be conveniently

25 shown on the overhead projector if there's one available. But I'm not

Page 19949

1 going to take time while we do that.

2 MR. NICE: Have you got a spare copy of the report, page 13 of the

3 addendum page 9?

4 Q. If the Chamber looks, while we're putting it on the overhead

5 projector, at page 13, figure 10 -- page 9 of the corrigendum -- we don't

6 have a spare copy of the original report at the moment, so this may be an

7 incomplete exercise.

8 But looking at page 9 of the corrigendum and page 13 -- sorry,

9 page 14 of the original report, we can see here what to the untrained eye

10 will look an identical top line; correct?

11 A. Yes, the top line is identical.

12 Q. People leaving their homes.

13 A. Yes.

14 Q. The bottom line, which is called "Residuals," is different on the

15 part post the 11th of May, i.e., the period for which you got additional

16 material about NATO airstrikes. That's visible to the naked eye. Also

17 visible to the naked eye, if one looks, for example, at the period the

18 24th of March to the 6th of April on the Residuals line, is the fact that

19 that line is a bit different. Not very much different but a bit

20 different.

21 JUDGE KWON: I'm sorry, but are we looking at figure 10 or 11?

22 MR. NICE: Figure 11.

23 JUDGE KWON: Figure 11.

24 MR. NICE: Page 14 on the original. And figure 11, page 14, shown

25 on page 9 of the corrigendum.

Page 19950

1 Q. So even the -- put it this way, Residuals line for the -- for

2 phase 1, 24th of March to 6th of April, seems to have changed a bit, but

3 you didn't have any additional material about NATO bombing because there

4 wasn't any for that period.

5 A. Mm-hm.

6 Q. Can you just explain in layman's terms why it is that some

7 material that came to you about the period post the 11th of May, or

8 thereabouts, affects the look of the line as early as 24th of March?

9 A. Yes. A statistical model is an equation or set of equations

10 derived from data, and the residuals here are the result of the

11 statistical model that we built. Adding data for this later period

12 changes the equations and so also changes the estimates that we would make

13 for the earlier period. Once the equations have changed, that change will

14 affect the entire line. So the line itself is not -- is the product of

15 the changes throughout the -- throughout the model that result from

16 changes in data only at the very end.

17 Q. Thank you. I'm going to come to the result of your additional

18 materials later, but let's go to the second piece of additional material

19 that you had to deal with. Following your giving of evidence, did it

20 become clear that some of the data upon which you relied was subject to

21 Rule 70 of the procedures -- of the Rules of Procedure and Evidence of

22 this Tribunal?

23 A. Yes.

24 Q. There being no release from the provisions of Rule 70, that is

25 therefore material that although you had had access to it, you shouldn't

Page 19951

1

2

3

4

5

6

7

8

9

10

11

12 Blank page inserted to ensure pagination corresponds between the French and

13 English transcripts.

14

15

16

17

18

19

20

21

22

23

24

25

Page 19952

1 have had access to?

2 A. That's correct.

3 Q. Did you rerun your tests, deleting that material?

4 A. Yes, we did.

5 Q. Was there a total of 17 records that had to be deleted?

6 A. That's correct.

7 Q. But was it only three of those that had any information of

8 relevance to your analysis?

9 A. That's correct.

10 Q. A third change can be understood by those with the appropriate

11 technical expertise at page 50 of the original report. We've got a spare

12 copy of that. We'll lay it on the overhead projector to see exactly what

13 you're saying, just page 50.

14 The line that the Judges need to look at is the line in the middle

15 of the page where you dealt with the procedures you adopted and in

16 particular how you'd determined to make a model choice for two-day

17 estimates. And in the middle of the page we see the line, "Choose the

18 model with the lowest adjusted Pearson chi-squared statistic." On review

19 of all your materials and tests, did you discover that that line was to a

20 degree inaccurate?

21 A. Very slightly, yes.

22 Q. Because?

23 A. Instead of the adjusted chi-square statistic, we had used a raw

24 chi-square statistic to make the selection for that component of the

25 estimates.

Page 19953

1 Q. We're not going to attempt in the time available a detailed

2 understanding of what either a Pearson or a raw chi-squared statistic is,

3 but in layman's terms, can you describe what this statistic did in the

4 process of preparing this materials, and then we'll have a look at the

5 consequences of the change of choice.

6 A. Mm-hm. As we did these estimates, we had to produce many

7 different estimates for each point in time, each two-day period. We did

8 so in order to explore the particular intricacies of data that had given

9 rise to that estimate. We then had to select the best model there. There

10 are many ways to do that. We felt that the best would be to express a

11 scientific value which states that if you have several different possible

12 explanations, scientific explanations for material, then all else being

13 equal, the simplest of those explanations is to be preferred. It's called

14 Occam's razor. More formally it's called parsimony. The adjusted

15 chi-squared statistic expresses that scientific value. It incorporates

16 this notion of parsimony or simplicity into the calculation. We would

17 then prefer that to other measures for selection.

18 Q. Having stated in the report at page 50 that you had chosen the

19 model with the lowest adjusted Pearson chi-square statistic, you then

20 discovered that in fact ...?

21 A. We had used the raw chi-square statistic for that component of the

22 calculations, for the piece that's described here on page 50 for the

23 two-day estimates.

24 Q. Given that for reasons you've identified, namely parsimony, as you

25 describe it, the other statistic was your preferred choice, did you rerun

Page 19954

1 the materials with the other statistic in place?

2 A. Yes, we did.

3 Q. Did that bring some change to the results?

4 A. There is a change. It's extremely small. It cannot be seen

5 easily in the graphs, but it can be seen in the numeric tables.

6 Q. And that's, therefore, the last page we'll look at, which in the

7 corrigendum is on page 11. And that itself tells us we can find the

8 original chart for which this is a replacement, as it were, at page 58 of

9 the report.

10 And the Chamber may recall, looking at page 58 of the report, that

11 the various figures revealed as regression coefficients were statistically

12 of no consequence save where they have asterisks beside them. Would that

13 be correct?

14 A. That's correct, yes.

15 Q. The Chamber may, I think, find it annotated its papers halfway

16 down the page, opposite "KLA (battle)" with an annotation to the effect

17 that the third entry, 2.728,6 should have an asterisk on it because,

18 broadly speaking, the figure in brackets is less than half of the figure

19 2.728. Is that correct, Dr. Ball? I certainly marked mine as being

20 asterisked whereas --

21 A. Yes. Yes, that's correct.

22 Q. It may be that the Judges will have done the same thing.

23 But in any event, it was only those with an asterisk beside them,

24 and although the figure is not precise - and you can explain this again in

25 the way that you did before - these figures only become significant if

Page 19955

1 they are very approximately twice the figure in brackets, which is the --

2 tell us, what's the figure --

3 A. The figure in brackets is the standard error. Twice the standard

4 error -- plus or minus twice the standard error is sometimes called the

5 margin of error. In order for something to be -- a measure to be

6 meaningful, it has to be sufficient to exceed the margin of error. The

7 margin of error must not overlap 0. If it does, then in formal language,

8 we cannot distinguish the measure from 0 and so therefore must draw no

9 interpretation from it.

10 Q. So to remind the Judges, looking at the original report, page 58,

11 figure 19, and going to the left of the figure on which I've concentrated,

12 13.3 being nothing like as much as twice 12.2, is of no significance; 34.7

13 being nothing like twice 32.1 is also of no significance.

14 A. Right.

15 Q. When you reran the model using the different chi-square statistic,

16 you produced the chart that we have on page 11 of your corrigendum.

17 A. Yes. It incorporates all three of the changes we've discussed

18 this morning.

19 Q. And what is it that we now notice about the numbers beside which

20 there are asterisks?

21 A. There are several new -- newly significant numbers that result, I

22 think primarily from the addition of the NATO data after the period when

23 migration and killing occurred. These are these three numbers here. It

24 is of interest that they are all negative, indicating a negative

25 relationship between the occurrence of NATO airstrikes and the occurrence

Page 19956

1 of killings in those periods and regions.

2 JUDGE KWON: Could you point at the three numbers once again.

3 THE WITNESS: This one, this one --

4 JUDGE KWON: Yes.

5 THE WITNESS: -- this one.

6 MR. NICE:

7 Q. Is there any way we can see the consequence of this on any of the

8 graphs? You say the consequence is very slight.

9 A. Yeah, it's very difficult to see. The -- excuse me. There is a

10 very close comparison of figures 10 and 11. Comparing the bottom lines in

11 each of those against the originals, we'll find that these two figures --

12 to these two figures, the bottom lines in figures 10 and 11, very

13 slightly, more closely approximate the top lines than they do in the

14 original report, but it's, as I said, very, very small.

15 Q. I think that your drawing that to our attention provides a

16 suitable route to really the last question I want to ask you, which is to

17 remind us of what a residual is and what its closeness to the top line,

18 which is the -- in this case, people leaving their homes, if we're looking

19 at figure 11, what the significance of vis-a-vis its being close in shape

20 to the top line.

21 A. As I said earlier, a statistical model is a set of equations, one

22 or more equations, derived from data which we use to make predictions,

23 numeric predictions about something we observe. In figure 10, for

24 example, we've built statistical -- a statistical model which predicts for

25 each two-day period how many people were killed. The Residual line

Page 19957

1 underneath is the result of subtracting the prediction from the top line.

2 The purpose of such an analysis is to see if the prediction has been a

3 good one. Has it approximated -- has it told us something about the top

4 line? Finding that the residual pattern closely tracks the original line

5 indicates that the prediction has been a poor one; it has not well

6 described the original.

7 When we say that we have failed to explain the original pattern,

8 we make that conclusion on the basis of the residual being essentially, in

9 an interpretive sense, identical to the original pattern. So we have

10 failed to explain the original pattern. Since the statistical model

11 incorporates our knowledge -- our statistical knowledge about KLA and NATO

12 activity, what we say then is that KLA and NATO activity failed to

13 explain, in this case, the number of killings in each two-day period. It

14 is therefore that the model gives us the basis for rejecting the

15 hypotheses that the KLA activity or NATO activity in our model could be a

16 cause of killing. So the closeness of the two lines is a way of saying

17 that the data used to create the bottom line does not explain the top

18 line.

19 Q. I said that was the last question, but I think, looking at page 2

20 of your corrigendum and recognising that many people here or viewing will

21 not have had the opportunity of going with you over the techniques you

22 employed in more detail, it may be helpful to put this material in even

23 more lay terms.

24 A. Mm-hm.

25 Q. Did the new material in raw terms apparently say something about

Page 19958

1 whether the number of deaths increased or declined as NATO airstrikes

2 increased or declined?

3 A. The -- adding the data from late May and early June creates in the

4 model a negative correlation between NATO activity and killings. Formally

5 the interpretation would be that on a given two-day period, on average

6 there would be 7.8 or approximately 8 fewer killings for each NATO

7 airstrike that occurred in that two-day period. And there would be 14

8 fewer killings in the same region, in the same period -- excuse me, in the

9 subsequent period as a result of each additional NATO airstrike. Overall,

10 the interpretation is that at times and places where there are more

11 killings, there tend to be fewer airstrikes, and conversely, when there

12 are more airstrikes, there tend to be fewer killings.

13 Q. Now, for anyone seeking to argue that the NATO airstrikes were

14 irrelevant to the killings, this raw finding or raw conclusion would seem

15 to be favourable to that conclusion, but you make the point contrary to

16 that, that it's really coincidental.

17 A. Yes. It's clear from the various graphs that most of the

18 migration killing occur in late April -- excuse me, late March through

19 early to mid-April. Most of the NATO airstrikes occur in late May and

20 early June. We therefore think that, although the statistical models will

21 see that as a negative correlation, because much later in the period

22 there's more airstrikes and fewer killings, more airstrikes and fewer

23 migrations, we believe that it is illogical to argue that airstrikes that

24 occur in late May and early June can somehow be interpreted as having

25 prevented or stopped killings that occurred weeks earlier. So we

Page 19959

1 interpret this as a statistical coincidence.

2 Q. In sum, do the -- does the additional material about airstrikes,

3 the deletion of the three pieces of material that were Rule 70, or the

4 rerun using the different coefficient change your original conclusions at

5 all?

6 A. No.

7 Q. Thank you.

8 JUDGE MAY: Yes, Mr. Milosevic.

9 Cross-examined by Mr. Milosevic:

10 Q. [Interpretation] Mr. Ball, the title page of your report of the

11 15th of November says the following: "The American Association for the

12 Advancement of Science, American Bar Association, Central and East

13 European Law Initiative." That's right, isn't it?

14 A. Yes.

15 Q. However, already on the next page - and the number of that page is

16 03079044 of the B/C/S version, but it is page 2 anyway of your text - it

17 says the following: "The materials contained herein should not be

18 construed to be the view of the American Association for the Advancement

19 of Science, Science and Human Rights Programme, or this third institution,

20 the American Bar Association," et cetera. That's right, isn't it?

21 A. That's correct.

22 Q. Is it also correct that on that same page you state that

23 interpretations and conclusions do not represent the positions of the

24 organisations mentioned and that they have not been allowed either by the

25 board of governors of the American Bar Association, et cetera? Is that

Page 19960

1 roughly what it says? "Views of the AAAS board council, the CSFR, or the

2 members of the association."

3 A. That's correct.

4 Q. And at the end it says, "Nothing contained --" and I'm quoting

5 from the B/C/S version here. "Nothing contained in this publication is to

6 be considered as the rendering of legal advice for specific cases, and

7 readers are responsible for obtaining such advice from their own legal

8 counsel. This publication and any forms and agreements herein are

9 intended for educational and informational purposes only." Is that so,

10 Mr. Ball?

11 A. That's correct.

12 Q. Now, tell me this, please: As you're a man of science, what

13 value, in view of all these very explicit reservations that have been

14 proclaimed here, do you consider that your material has in proving the

15 indictment by the other side here?

16 JUDGE MAY: That's not a relevant question. What you're limited

17 to is asking this witness about the evidence he's given, rather than a

18 polemic of that sort.

19 THE ACCUSED: [Interpretation] Very well, Mr. May. If the question

20 is not relevant, let's move on to others which you might consider

21 relevant.

22 MR. MILOSEVIC: [Interpretation]

23 Q. Mr. Ball, you placed the focus of your research exactly on the

24 period of 78 days, the 78 days of the NATO aggression. That's right,

25 isn't it?

Page 19961

1 A. [No audible response]

2 Q. From the 24th of March, that is, until the first days of June;

3 right?

4 A. Yes, from late March to early June.

5 Q. Yes, that's right. And then you divide that period of time into

6 phases, stages, and you established movements, values, estimates of the

7 numbers of people leaving their homes or who were killed; is that right?

8 A. That's correct.

9 Q. In doing so, you use -- for all the casualties of the war, you

10 used the term "killed persons"; right?

11 A. For the deaths of ethnic Albanians, we used the term "killed

12 persons." Not for all casualties of war. That's explicit in both

13 reports, I believe.

14 Q. Fine. Very well. Now, as you set this framework for yourself

15 from the 24th of March to the first few days of June, and then you go on

16 to observe that looking at movements within those frameworks your basic

17 conclusion represents the following: That the activities of the KLA and

18 NATO were not the cause of human casualties. That is your main message;

19 right, Mr. Ball?

20 A. The conclusion is that activities of the KLA and NATO are not the

21 cause of the deaths of ethnic Albanians, as represented in these

22 estimates, nor are they the cause of the mass migration patterns also

23 described here.

24 MR. NICE: Your Honour, before the --

25 THE ACCUSED: [Interpretation] That's fine.

Page 19962

1

2

3

4

5

6

7

8

9

10

11

12 Blank page inserted to ensure pagination corresponds between the French and

13 English transcripts.

14

15

16

17

18

19

20

21

22

23

24

25

Page 19963

1 MR. NICE: Before the accused goes on, I'm reminded helpfully by

2 Mr. Saxon and I should have reminded you earlier, that the leave given for

3 cross-examination by your order of the 25th of February of this year is

4 very narrowly expressed, and it's that he should be available for

5 cross-examination on three issues: Source, authenticity, and reliability

6 of the new data; two, reason for and the precise effects of the using of

7 the adjusted Pearson chi-squared statistical method; and three, the basis

8 for the different figures provided in the revised tables at pages 313 of

9 the corrigendum -- 3 to 13 of the corrigendum. So that is the order of

10 the Chamber.

11 JUDGE MAY: Thank you. Yes. Mr. Milosevic, you've heard that.

12 Move on to some relevant matter.

13 THE ACCUSED: [Interpretation] Very well, Mr. May. I assume that

14 these are relevant things.

15 MR. MILOSEVIC: [Interpretation]

16 Q. Now, tell me this, please, Mr. Ball: Regardless of the fact that

17 the opposite side interrupted us, I nevertheless am sure that you're

18 following what I'm asking you, and this is it: How do you know from the

19 aspects of statistics -- because you have made this framework for yourself

20 from the end of March to the first days of June, that is where you place

21 your research, within that framework. From the statistical standpoint,

22 how do you explain the fact that before the war began there was -- there

23 were no casualties of this kind?

24 JUDGE MAY: That's not a matter for the witness. He's purely

25 produced this report, and your cross-examination should be based -- if

Page 19964

1 you've got any questions about the changes in the report, the corrigendum,

2 you can ask them. The point is you've already cross-examined him once

3 extensively, so we can't go over that again. Now, have you got any

4 questions -- do you have any questions you want to ask about the

5 corrigendum?

6 THE ACCUSED: [Interpretation] I do. As the corrigendum has been

7 provided for this purpose, then I assume, Mr. May, that it is quite a

8 legitimate question to ask the author these questions. Despite all the

9 restrictions and limitations we have noted, he stands by the fact that

10 this publication can be used in these proceedings, the ones conducted here

11 and now.

12 MR. MILOSEVIC: [Interpretation]

13 Q. That's right, isn't it?

14 A. Yes.

15 Q. And in that regard, it is not vital that the casualties have all

16 been situated during a time of war, whereas before that these casualties

17 did not occur.

18 JUDGE MAY: These are not matters for the witness.

19 THE ACCUSED: [Interpretation] Very well. Fine. So just the

20 corrigendum, is that it, Mr. May?

21 JUDGE MAY: Yes.

22 MR. MILOSEVIC: [Interpretation]

23 Q. On page 03079045, point 2 of the corrigendum, you state that each

24 of the individual corrections described below was small, and as we

25 discussed it earlier, their combined impact was negligible. That's what

Page 19965

1 you state; right?

2 A. Yes.

3 JUDGE MAY: This is so we --

4 MR. MILOSEVIC: [Interpretation]

5 Q. But you also --

6 JUDGE MAY: This is page 1 of the report.

7 THE ACCUSED: [Interpretation] Yes. Very well.

8 MR. MILOSEVIC: [Interpretation]

9 Q. Then you go on to say the following. It is in section 2.2. There

10 are three dots, and the second dot reads as follows: "Pursuant to Rule 70

11 of the ICTY Rules of Procedure and Evidence -" of this institution, that

12 is - "we were asked by the OTP to drop 17 records from the data they

13 provided to us about activity by the KLA because the information came from

14 confidential sources." Is that so?

15 A. Yes.

16 Q. Now, answer me this, please: By including these information --

17 this information in your analysis, would you in any way whatsoever have

18 disclosed the identity of the sources of that information? Because here

19 you're dealing with statistical indices, a statistical representation, in

20 fact, of what you are following in terms of numbers. So had you

21 introduced into the analysis what you were not allowed to do so by the

22 opposite side over there, because it was confidential data and sources, as

23 you say in your corrigendum, in order to disclose the identity, would the

24 identity of the source information be disclosed had you used what the

25 opposite side did not allow you to use?

Page 19966

1 JUDGE MAY: Can you answer that, or not, Dr. Ball?

2 THE WITNESS: It's -- all I can say is that the OTP provided me

3 with the identification numbers of the records to delete; I deleted them.

4 Three of those records were relevant to this analysis.

5 MR. MILOSEVIC: [Interpretation]

6 Q. All right. Fine. Thank you. That will be sufficient as a

7 response to my question.

8 Now, the substance and essence of your corrigendum in fact relates

9 precisely to this piece of information: That according to Mr. May's

10 assessment, we did not use adequately but I assume you'll confirm that

11 that does represent the substance in the period you're dealing with, that

12 is to say, the time of the NATO aggression. So in that period of time,

13 the relationship and ratio between killings and NATO bombings is reversely

14 proportionate; that is to say, the number of the killings of Albanians is

15 reduced with the intensity of the bombing as it increases and vice versa,

16 is increased with the decrease of NATO aggression and bombings. Is that

17 what you're claiming?

18 A. I'm a bit confused by the explanation. Perhaps I can -- can

19 clarify. We interpret this as coincidental. Our observation is that

20 there is a negative association between the patterns if one interprets the

21 statistics literally. As I explained during my direct examination,

22 however, we believe this to be a coincidence of when these two processes

23 occurred, with NATO bombing occurring weeks later than the bulk of killing

24 and migration.

25 Q. So you consider this to be coincidental.

Page 19967

1 Now, could you give us the source you used for your information

2 when you conducted this analysis and the conclusions you arrived at. What

3 source?

4 A. The same sources were used as in the original report. They are

5 listed in the original report. I'll give you the page. It's Appendix 3,

6 page 63 and 64.

7 Q. And tell me this: In those points, which data did you include

8 into your analysis relating to the distribution, composition, types of

9 units of the Ministry of the Interior and the Army of Yugoslavia at the

10 material time and material period in the given regions? Because you have

11 northern, eastern, southern, and so on, those different regions. So which

12 data of that type did you use and incorporate?

13 A. We include no data on Yugoslav forces or force movements. It is

14 for that reason that there is no statistical analysis in this report of

15 Yugoslav activity. We did observe one coincidence, which was that after

16 the Yugoslav government said on television on the evening of April 6th

17 that they would observe a cease-fire, we see that killing and migration in

18 the subsequent four days after that announcement are at their lowest point

19 since the beginning of the conflict. At that same period, NATO and KLA

20 activity increase greatly relative to their earlier rates.

21 However, as we observe in the original report, that is suggestive

22 but by no means proof of -- of this activity, that the Yugoslav government

23 was the cause of killing and migration. We simply observe that there is a

24 coincidence there that is interesting.

25 Q. An interesting coincidence. Right. But it's not proof of the

Page 19968

1 assertion that the activities of the Yugoslav authorities were the reason

2 for the migration; is that what you say, Mr. Ball?

3 A. I think more formally we should state that the coincidence of the

4 Yugoslav announcement of the cease-fire with the dramatic reduction in

5 killing and migration is consistent with the argument that the Yugoslav

6 government was the cause of killing and migration. It is not proof.

7 Statistics do not offer positive proof. Statistics can reject hypotheses.

8 But when we find statistical patterns that are consistent with hypotheses,

9 we say just that, that they are consistent with, or sometimes the formal

10 language is that they are suggestive of agreement with the hypothesis or

11 argument.

12 Q. All right. Now, movements of numbers of people who were fleeing

13 from the war-inflicted areas, the number of refugees and people fleeing

14 and so on, was that one of the topics of your analysis as well? Were you

15 asked to look at that topic?

16 A. I was not asked to look at it, but yes, we did look at it. That

17 was the basis of an earlier report, which we discussed during my testimony

18 a year ago, entitled "Policy or Panic." The analysis of migration is also

19 to be found in many of the graphs in our report to the Tribunal last year,

20 as well as in, for example, figure 2 on page 3 of the report we are

21 discussing this morning.

22 Q. Let's take any page. For example, page 2 -- or rather, figure 2,

23 the estimated total refugee migration and killings over time. It's on

24 page 3. And then you can see phase 1, phase 2, and phase 3. And you say,

25 "People leaving their homes." That's what it says here; right?

Page 19969

1 A. Yes.

2 Q. And then according to statistics, in phase 1, where according to

3 you was the lowest intensity of the NATO bombing; right? Phase 1 was the

4 lowest NATO bombing intensity; is that right?

5 A. We have not argued that, but there is lower intensity during that

6 period than in the later periods.

7 Q. All right. That's very good. So in phase 1, people flee the

8 most. That's when most of the migrations and fleeing takes place. Most

9 people -- lots of people are leaving their homes during phase 1; right?

10 A. That's correct.

11 Q. You know, Mr. Ball, I'm sure, what "Homo sapiens" means.

12 JUDGE MAY: Mr. Milosevic, let's move on. You've got a quarter of

13 an hour more. That will give you, we think, sufficient to cross-examine

14 on this corrigendum.

15 MR. MILOSEVIC: [Interpretation]

16 Q. Mr. Ball, the beginning of the bombings, is it logical to assume

17 that the beginnings of this would trigger off the effect where the largest

18 number of people who are afraid and who cannot know what the intensity of

19 the bombings will be in future --

20 JUDGE MAY: You misunderstand his evidence. His evidence is

21 mathematical. He has come to -- he has done various tests and he's come

22 to various conclusions. You can ask him about that. The questions you

23 are asking him are matters which you'll have to address to us in due

24 course, as to why you say this refugee flow occurred. What may seem

25 common sense or something like that is not the point. The point is to ask

Page 19970

1 him about his own model and his evidence. It's an opinion. He's an

2 expert. We will have to consider what weight to give to it.

3 Now, if you've got any more questions about his report, you can

4 ask them, or particularly about the corrigendum; otherwise, we'll bring

5 this to an end.

6 THE ACCUSED: [Interpretation] Very well. Mr. May, here we have a

7 question about models, or rather, the logics of thinking that Mr. Ball

8 applied.

9 MR. MILOSEVIC: [Interpretation]

10 Q. And I'm asking you, Mr. Ball, did you take into consideration in

11 your model and the data and information you present fear, the fear that

12 bombing produces in people?

13 JUDGE MAY: That's precisely the sort of question which I've told

14 you you can't ask him. He's not here to give evidence about psychology.

15 He's giving evidence about a report.

16 Now, it sounds as though you've really got no more to ask him on

17 the corrigendum, so we might as well move on and not waste further time.

18 THE ACCUSED: [Interpretation] Well, let's move on. I have not

19 used up all my time yet, Mr. May.

20 MR. MILOSEVIC: [Interpretation]

21 Q. Mr. Ball, tell me this, please: In any one of your figures,

22 graphs, in addition to the curves that we see according to your

23 measurements show the trend of migration, that is to say, the people

24 leaving their homes, do we also see a line which would indicate the

25 intensity of the NATO bombings themselves?

Page 19971

1 A. In these graphs, there is no such observation.

2 Q. Why not?

3 A. Because we have incorporated the analysis of the NATO patterns in

4 the statistical model, which I discussed during my direct examination.

5 So, for example, the effect -- the statistical effect of those patterns,

6 of both the NATO airstrikes and the KLA activity, can be seen in, for

7 example, figure 10 in the Residual line, which we have already covered;

8 similarly in figure 11, also in the Residual line, which we have covered;

9 and then in more precise technical detail in figure 19, page 11, entitled

10 "Regression coefficients." It is in particular the coefficients for each

11 of the KLA measures and the NATO measure that the effect on killing or

12 migration of the KLA or NATO activity can be seen.

13 Q. All right. And tell me this, Mr. Ball: What were your data

14 sources for KLA activities?

15 A. We covered this extensively in my original testimony last year,

16 but to review, those sources are shown in the Appendix 3 -- I'm sorry, I

17 guess I've already given you that page number. And perhaps we can look at

18 them one at a time, if they're of interest, but they're listed there.

19 Q. As documents exist which indicate KLA activity, which is in

20 possession of the opposite side as well, there are also documents which

21 indicate the orders given by the KLA to the population, telling them to

22 leave the territory of Kosovo and move to Macedonia, Albania, and

23 Montenegro. Did you take into consideration those documents too when you

24 conducted your analyses of the effects of KLA activity?

25 THE ACCUSED: [Interpretation] I'm asking Mr. Ball, Mr. May,

Page 19972

1 whether he took into consideration certain documents. That's quite a

2 legitimate question, I assume.

3 JUDGE MAY: You cross-examined extensively a year ago, and we've

4 heard all this before. But yes, since it's been asked, perhaps you would

5 deal with it.

6 THE WITNESS: We did not take into consideration any documents

7 from any party that expressed intention, in statistical terms. The only

8 intention we considered was to -- was not statistical but, rather, just to

9 observe the dramatic decline in killing and migration that occur on the

10 night of April 6th/April 7th.

11 MR. MILOSEVIC: [Interpretation]

12 Q. All right. In your conclusions, you state that you're continuing

13 your investigation of the data using more complex methods; is that right?

14 A. Yes, it is.

15 Q. This observation of yours, can I interpret it as your view and

16 assessment that not even from your standpoint is this analysis

17 comprehensive and all-embracing, nor that you used certain more complex

18 and reliable methods?

19 A. For scientific publications, the conclusions -- the substantive

20 conclusions here I believe are no longer in question. We've already

21 published these results in a peer review journal, so that's not the

22 question.

23 However, the data are uniquely interesting from a scientific

24 perspective and invite substantial additional kinds of experimentation.

25 We have published the data on the Internet specifically to invite the

Page 19973

1

2

3

4

5

6

7

8

9

10

11

12 Blank page inserted to ensure pagination corresponds between the French and

13 English transcripts.

14

15

16

17

18

19

20

21

22

23

24

25

Page 19974

1 scientific community to continue considering these -- these phenomena, but

2 I consider it unlikely in the extreme that any change in the

3 interpretation of the core hypotheses we have proposed here should emerge.

4 Quite the contrary. Our initial and much more detailed kinds of analysis

5 that we are beginning for scientific publication, we hope, have found

6 precisely the same results that are found here.

7 Q. Let's just clarify what we're talking about, not to speak of two

8 different things. When you say that you published that, observed that,

9 and so on, this relates to the meaning that was put forward on page 1 of

10 your report that the information contained and the positions are

11 exclusively used for education and information purposes, in order to

12 educate and inform; is that right? It's the last sentence, actually,

13 which says that: "This publication and any forms and agreements herein

14 are intended for education and informational purposes only." Before that

15 you say that it cannot be considered to be legal advice for specific

16 cases. And before that again, it states that it does not represent the

17 positions of the institutions you mention.

18 So when you say that you have concluded this portion, you're

19 talking about the scientific aspects of your analysis and checking out

20 certain statistical methods which you applied; is that correct?

21 A. I am a scientist; my colleagues are scientists, and of course what

22 we are doing is for scientific purposes. I believe that's my purpose here

23 today.

24 Q. Very well. And tell me, finally, to what extent the type of

25 sources of information influences any analysis, including your own. The

Page 19975

1 different types of resources and sources of information, to what extent

2 that has an influence on an analysis, any analysis, including your own.

3 JUDGE MAY: Can you answer that?

4 THE WITNESS: Sorry?

5 JUDGE MAY: Do you understand that question?

6 THE WITNESS: I think it requires a course of methodology to

7 respond to. It's not an -- not a question that can be answered easily. I

8 can try to give a very brief answer, if that would be useful to the Court.

9 JUDGE MAY: Well, since you've been asked, a brief answer, please.

10 THE WITNESS: Of course the sources of data and their type

11 influence our choice of statistical methods that should be used to analyse

12 them. In particular, when we have multiple projects that attempt to

13 enumerate deaths, we can use the method that's used here to compare those

14 multiple projects, determine which deaths have been reported in common

15 across the projects, and use that information to make an estimate of

16 deaths that have not been reported to any project. That is the basis for

17 our analysis of killings.

18 The purpose of using a method of that kind is explicitly to

19 understand how many people have not been reported -- how many people's

20 deaths have not been reported to any project. So this is one example of

21 considering the sources of data, in this case interviews by the ABA/CEELI,

22 Human Rights Watch, the Organisation for Security and Cooperation in

23 Europe, and the forensic reports of bodies exhumed and identified. These

24 four sources can be used with this method called "multiple systems

25 estimation."

Page 19976

1 MR. MILOSEVIC: [Interpretation]

2 Q. So only those four sources. Now, tell me, please, Mr. Ball:

3 These numbers, as far as I was able to understand from something you said

4 during the examination, they apply exclusively to Albanians; isn't that

5 right?

6 A. These four sources are used to estimate killings. Let's

7 distinguish that from data and analyses used to estimate migration

8 patterns.

9 To the second part of the question, yes, we have estimated only

10 the deaths of ethnic Albanians. That's, I believe, clearly explained in

11 the first report, where we explain the entire process by which we matched

12 the deaths across projects to determine which deaths are reported in more

13 than one of the projects. That's Appendix A in the first report.

14 JUDGE MAY: You can ask one more question.

15 MR. MILOSEVIC: [Interpretation] Very well. I'm sorry that I was

16 not able to find my way straight away. Because you say here people

17 leaving their homes and people killed, I assumed that you were referring

18 to all the people, not just ethnic Albanians. But do you think -- don't

19 you think that it would be essential, in order to see the effect of

20 everything that was going on, to cover all people? For example, 100.000

21 Serb refugees from Kosovo, or how many Serbs were killed in Kosovo, and

22 not just ethnic Albanians. In order to provide at least to some extent a

23 more objective presentation of the statistical data that you have

24 produced?

25 JUDGE MAY: Can you answer that or not?

Page 19977

1 THE WITNESS: I believe that using the data we have used is

2 sufficient to address the hypotheses we addressed, which is what caused

3 the killing and migration of ethnic Albanians.

4 JUDGE MAY: Very well.

5 Mr. Kay?

6 MR. KAY: Nothing further to add to previous cross-examination.

7 JUDGE MAY: Anything from the Prosecution?

8 We ought to -- we ought to exhibit the corrigendum, before that's

9 forgotten.

10 MR. NICE: Yes.

11 JUDGE MAY: It's 67 ...?

12 THE REGISTRAR: Your Honours, the corrigendum will be marked

13 Prosecutor's Exhibit 67.1, and the B/C/S translation will be 67.1A.

14 MR. NICE: Thank you.

15 Re-examined by Mr. Nice:

16 Q. Dr. Ball, you've been asked questions about the source of your

17 material. For NATO bombing, did you turn to material provided by

18 Yugoslavia itself?

19 A. Nearly all -- nearly all the data -- I'm sorry. Nearly all the

20 data for NATO bombing comes from Yugoslav sources.

21 Q. Any particular reason for using that, as opposed to any other

22 source?

23 A. My calls to the US Department of Defence were unanswered, and the

24 Yugoslav sources were published in press briefings and on the Internet, so

25 they were easily accessible. We also felt - and I believe we discussed

Page 19978

1 this last year - is that using the Yugoslav sources on airstrikes would be

2 the strictest possible test of the hypothesis that the NATO activities had

3 caused killing and migration, since it was some of those same sources that

4 had advanced that idea.

5 JUDGE MAY: Dr. Ball, that concludes your evidence. Thank you for

6 coming back again to add to it. You are free to go.

7 [The witness withdrew]

8 JUDGE MAY: Now, Mr. Nice, is there anything to raise before we go

9 back into closed session?

10 MR. NICE: I don't think so, no.

11 JUDGE MAY: We'll go into closed session.

12 [Closed session]

13 [redacted]

14 [redacted]

15 [redacted]

16 [redacted]

17 [redacted]

18 [redacted]

19 [redacted]

20 [redacted]

21 [redacted]

22 [redacted]

23 [redacted]

24 [redacted]

25 [redacted]

Page 19979

1

2

3

4

5

6

7

8

9

10

11

12

13 Pages 19979-20037 - redacted closed session

14

15

16

17

18

19

20

21

22

23

24

25

Page 20038

1 [redacted]

2 [redacted]

3 [redacted]

4 [redacted]

5 [redacted]

6 [redacted]

7 [redacted]

8 [redacted]

9 [redacted]

10 [redacted]

11 [redacted]

12 [redacted]

13 [redacted]

14 [redacted]

15 [redacted]

16 --- Whereupon the hearing adjourned

17 at 2.08 p.m., to be reconvened on Monday,

18 the 5th day of May, 2003, at 9.00 a.m.

19

20

21

22

23

24

25