U.S. Department of Justice

United States Attorney
Eastern District of New York

United States Attorney's Office
1 Pierrepont Plaza
Brooklyn, New York 11201

February 13, 1997

Michael R. Bromwich
Inspector General
U.S. Department of Justice
Room 4706
10th and Constitution Avenue, N.W.
Washington, D.C. 20530

Re: Draft Report on The FBI Laboratory: An Investigation into Laboratory Practices and Alleged Misconduct in Explosives-Related And Other Cases

Dear Mr. Bromwich:

This letter is submitted in order to comment on and correct certain errors1 and misimpressions created by that portion of the report prepared by the Office of the Inspector General on the FBI Laboratory relating to the Avianca case (the "Report"). While we do not profess to have the scientific expertise or training to evaluate the technical criticism levied at Special Agent Hahn's testimony, the Report does omit or misstate certain facts and as a result, may be misleading in its conclusions.

Essentially, there are several major problems with the Report. First, the Report is premised on a misunderstanding of the prosecution's case: contrary to the assumptions stated in the Report, the type of explosive used in the Avianca bombing was irrelevant and immaterial to


1The first error that needs to be corrected is the misspelling of the first and last names of former Assistant United States Attorney Cheryl Pollak (now a U.S. Magistrate Judge, Eastern District of New York). In addition, on the first page of the Preface, there is a reference to "two 1994 trials in a case related to the 1989 bombing of an Avianca Airlines flight in route from Bogota, Colombia to Miami, Florida." In fact, the plane was en route from Bogota to Cali, Colombia, not Miami.


either the prosecution or the defense case. In fact, had the prosecution been able to prove that dynamite was used, as the Whitehurst Memorandum suggests, the Prosecution's case would have actually been strengthened. Thus, the conclusion reached by the Report that Agent Hahn's alleged "errors tended to help the prosecution's case or rebut a defense" is erroneous.

In addition to this fundamental misconception, the Report: (1) misstates certain facts regarding the genesis and significance of the "Confessor's" statements; (2) fails to review the testimony of the other expert witnesses and thus, ignores the fact that Agent Hahn was proffered in large measure as a summary expert witness; (3) fails to adequately define certain terms and, as a consequence, appears to express opinions contrary to other evidence that does not appear to have been reviewed. Each of these issues is addressed in detail below. However, regardless of whether these specific concerns are ultimately addressed in the Report, the Report needs to be clarified as to its position on Agent Hahn's basic opinion -- namely, that an explosive device functioned on board the Avianca plane. As currently drafted, it is unclear whether the experts involved in drafting the Report have concluded otherwise.

A. The Type of Explosive Was Irrelevant

First and foremost, the Report suggests that the dispute between Agent Hahn and Agent Whitehurst regarding the nature and type of explosive used in the bombing of the Avianca plane was somehow material to either the prosecution or the defense case. It was not. Agent Hahn was called by the government primarily as a summary expert witness, to put into context the testimony of the various experts who testified before and after Agent Hahn and to provide the simple opinion that an explosive device functioned on board the Avianca aircraft, in a location over the fuel bladder in the wings, and that, as a result, the plane crashed, killing all of the passengers and crew members on board the plane. The type and nature of the explosive used was neither relevant nor material, nor even necessary, to prove the government's case.

In fact, the government could have chosen to present its case without ever calling Agent Hahn to testify. The defense had offered to stipulate to Agent Hahn's testimony that an explosive device had functioned on board the plane, resulting in the death of all of the individuals on board. This, coupled with proof of defendant's participation in the bombing,


would have been sufficient to establish the elements of proof necessary under the statutes charged.

More importantly, it was not an issue in the defense case either. Indeed, the defense in the case was not premised in any way on the nature of the explosive device. Rather, the defense was willing to concede the bombing of the plane, but they denied that Munoz Mosquera had anything to do with the bombing. The focus of the defense case was on the testimony of the government's twenty cooperating witnesses who tied Munoz Mosquera to the events; nothing in Agent Hahn's testimony was even remotely relevant to their defenses, as evidenced by the defendant's opening and closing statements.2 Thus, the conclusion set forth on page 39 of the Report that "[a]ll of these errors [of Agent Hahn] tended to help the prosecution's case or rebut a defense" is simply without merit and reflects a fundamental misunderstanding of the case.

B. A Finding That Dynamite Had Been The Explosive Used
Would Have Actually Strengthened The Prosecution's Case

The Report is also based on the mistaken premise that a finding that dynamite was the operative explosive in the Avianca bombing would have hurt the prosecution's case. To the contrary, had the government been able to corroborate Agent Whitehurst's opinion that a dynamite or ammonium nitrate-based explosive could have been used in the Avianca explosion, this would have actually strengthened the prosecution's case. Specifically, the government presented the testimony of cooperating witnesses who testified at trial about Munoz Mosquera's training and expertise in the preparation and placement of explosive devices, with specific reference to devices using dynamite. (Tr. at 3026, 3028-29,3030, 1238-1239, 4l6l-62).3


2 During his summation, counsel for defendant conceded that a bomb had destroyed the plane and argued only that Munoz Mosquera was not involved. Indeed, the only mention made of Agent Hahn in the defense summation during the second trial related to the fact that he was sent to Colombia to assist the Colombian National Police and the fact that the evidence that he and others collected disappeared from the Avianca hangar overnight. (See Transcript of Jasper Summation, dated December 15, 1994 at 4837).

3Since the Report is mainly critical of Agent Hahn's testimony in the second trial, references to "Tr.," refer to pages from the trial transcript from the second trial, unless noted


Indeed, Munoz Mosquera actually taught a course in the preparation of bombs using dynamite, with one witness describing in detail how Munoz Mosquera constructed a bomb using dynamite. (Tr. at 3628-29). Other witnesses testified about the Medellin Cartel's access to vast amounts of dynamite imported from Ecuador that were stored in a warehouse in Bogota. Tr. at 4175, 4220, 4221-22, 4250, 4252). Still other witnesses were called to testify regarding the use of dynamite by Munoz Mosquera and his group of "sicarios" (assassins) in other Cartel bombings that were specifically charged as overt acts in the conspiracy, including the bombing of Las Drogas de Rebaja, a relay station in Bogota, a truck bomb designed to kill General Maza Marquez,4 and the bombing of DAS headquarters, all of which involved bombs using dynamite or some type of ammonium nitrate-based explosive. (See Tr. 2220-22,2213,2281-83, 2294-5,2415, 3012,3045, 3051, 4174-5 4188, 4221).

Indeed, evidence that the same type of explosive was used in both the Avianca and the DAS bombings -- namely, dynamite or ANFO -- would have further corroborated the other witnesses' testimony and strengthened the inferences that the government was asking the jury to draw -- that both bombings were done by the same group, led by Munoz Mosquera. Thus, if there had been any scientific basis for claiming that dynamite or any ammonium nitrate-based explosive was used in the bombing of Avianca, it would have provided a further basis for tying Munoz Mosquera to not only the bombing of the plane, but to the DAS bombing which was charged as an overt act, and to the other bombings charged in the indictment as well.

By contrast, the government had no testimony or evidence suggesting that either Munoz Mosquera or the Cartel had access to Semtex, RDX or PETN.5 Nevertheless, because the



4The government presented the testimony of a Colombian member of the bomb squad responsible for defusing the truck bomb and hundreds of other similar bombs in Bogota during that period. His testimony included an explanation of the construction of the truck bomb, illustrated with actual photographs of the dynamite used. (Tr. at 2280-95).

5Apparently, the Memorandum of Interview("MOI") reflecting Ms. Wilkinson's interview with representatives of the Inspector General's Office suggests that a cooperating witness testified that the Cartel often used Semtex. Ms. Wilkinson has advised me that she did


chemical analysis of the residues found on the fuel bladder of the plane, as explained to us by Agent Hahn, showed the presence of these chemicals, with no evidence of dynamite or an ammonium nitrate-based explosive being found in the wreckage of the plane, the government presented its case in accordance with the forensic evidence as we found it.

Indeed, given the fact that there was no residue of ammonium nitrate or dynamite found in the plane, the government, had they called Agent Whitehurst to testify, might have been accused of attempting unfairly to buttress the government's case with speculative and uncorroborated opinion testimony. Particularly in light of the criticism leveled at Agent Whitehurst's conclusions, and the speculative nature of his opinion, had the government elicited the testimony regarding the potential use of dynamite or an ammonium nitrate-based explosive as suggested by the Report and attempted to tie that opinion to the other evidence in the case, the government would have justifiably been subject to serious criticism. Thus, although Agent Hahn was extensively cross-examined on the availability of RDX, PETN and Semtex in South America, with a focus being access to these materials by terrorists in other parts of the world (Tr. at 2938-2942),6 we believe that it was more prudent for the prosecution to present its case in accordance with the physical evidence found, rather than argue the possibility that dynamite was used. Even though the possible use of dynamite was consistent with our other witnesses' testimony, we had no physical forensic evidence to support that claim.


not make such statements during her interview and perhaps the investigators misunderstood her discussion of the Medellin Cartel and its use of explosives. As stated above, several cooperating witnesses did discuss the terrorist training course and Munoz Mosquera's attendance at the course. Indeed, one of the key witnesses testified that Munoz Mosquera was involved in training other participants in the use of explosives, specifically, dynamite. This testimony supported the government's theory that Munoz Mosquera was knowledgeable about explosives. However, no witness ever suggested that the Cartel or Munoz Mosquera used or had access to Semtex.

6The defense theory at trial was that many, if not all, of the terrorist activities attributed to the Cartel by the government's witnesses were in fact the work of leftist guerrillas, such as M-19 and FARC, operating in Colombia at the time. To the extent that the defense was able to suggest the use of Semtex by these guerrilla groups and other terrorists not with the Cartel, Agent Hahn's testimony actually assisted the defendant's theory of the case.


Similarly, while we are not in a position to evaluate whether Agent Hahn was in error in that portion of his testimony that tied the pitting and cratering to a "high explosive,"7 if anything, his testimony, to the extent it seemed to eliminate the use of dynamite, actually provided the basis for a defense challenge to Munoz Mosquera's involvement in the Avianca bombing.8

While we recognize that it is often difficult in preparing a Report of this type to become familiar with the evidence and arguments presented during the course of a lengthy trial involving over forty witnesses and more than eight weeks of trial, the Report as now drafted suffers from the fact that such a comprehensive review was not conducted.9

C. The "Confessor"

A second area in which the Report is seriously misleading as now drafted relates to the statements of the individual referred to in the Report as the "Confessor" -- Carlos Mario Alzate, a/k/a "Arete." Contrary to the impression left by the Report, Arete's statements were never


7Walter Korsgaard, formerly FAA Program Manager and National Resource Specialist for Aviation Explosives Security, prepared a report entitled "Technical Investigative Findings of HK 1803" ("Korsgaard Report"), based on his investigation of the Avianca crash. It should be noted that Walter Korsgaard supported Agent Hahn's belief that a "high explosive" was used. In his Report, he specifically describes finding a "piece of fuselage skin with similar high explosive hot gas cratering effects" which he explained as "further substantiating the presence of an IED as the initiating event of the destruction of HK 1803." (Korsgaard Report at 3). As Korsgaard's Report makes clear, Agent Hahn's conclusion as to the use of a "high explosive" was not reached in a vacuum nor was it based solely on the pitting or cratering or the I-beam information; it was based on a consideration of all the evidence and on the collective views of other experts.

8Indeed, the Report notes that certain types of dynamite produce the same type of pitting and cratering effect as the high level explosive described by Agent Hahn. (Report at 9). Unfortunately, the Report fails to disclose what specific types of dynamite it is referring to or whether such types of dynamite were available in Colombia in 1989. Without this information, it is difficult to evaluate the Report's conclusion that the prosecution should have introduced testimony regarding this potential use of dynamite at trial.

9Because we were not permitted to review the MOIs summarizing the interviews conducted by representatives of the Inspector General's Office prior to the drafting of the Report, we cannot be sure there are not other inaccuracies or misunderstandings reflected in the MOIs.


admitted at trial; he never testified at either trial and never even came close to being called as a witness.

Arete's statements regarding the bombing of the Avianca plane were first brought to the attention of the Court by defendant's attorneys in April 1994 prior to the start of the first trial.10 Defense counsel had interviewed Arete extensively in Colombia and were fully aware of his claims prior to the receipt by the Court of the letter from the Attorney General of Colombia. Indeed, defense counsel hand-delivered the letter to the Court. At the time of his so-called "confession," which to this day has remained sealed and was never disclosed to the government or the Court, Arete was confined in a high security prison in Colombia on charges brought by the Colombian government relating to his narco-terrorist activities. He gave his statement to the Colombian officials in exchange for a promise of a lenient sentence. However, since he was in prison in Colombia at the time, it was impossible for him to travel to the United States to give sworn testimony. Not only would the government of Colombia have had to agree to release him from jail to allow him to travel to the United States to testify, but the government of the United States would have had to grant him full immunity for the numerous criminal activities for which he was wanted in the United States, including the bombing of the Avianca plane to which he had confessed, as well as other acts of terrorism. Since the Department of Justice was not about to grant immunity to a confessed murderer and terrorist, the only alternative was to have the attorneys for both sides of the case travel to Colombia for a deposition of Arete. Although granted time and an opportunity to 'pursue this avenue, the defendant's counsel dropped the matter and never made any further requests regarding Arete's testimony.11 Thus, to conclude in


'0At the time the issue was raised, the defendant sought to postpone the trial. The prosecution's belief is that when his request for postponement was unsuccessful, defendant dropped the issue of Arete because the defense was never seriously considering him as a witness.

11Indeed, after the initial mention of Arete's alleged confession shortly prior to the first trial, there was never any issue raised regarding Arete's statements relative to the second trial. It was for this reason and the fact that the issue was neither relevant nor material to either the government's or the defendant's case that AUSA Wilkinson who prepared and presented Agent Hahn as a witness during the second trial did not discuss the Whitehurst Memorandum nor ask him questions about it during.the second trial. (See Report, note 18 at p.18).


the Report in several places that Agent Hahn's testimony was used to "rebut" the Confessor's testimony or to "rebut" the defense case leaves the misimpression that Arete's statements were somehow placed before the jury or that the defense somehow presented a "case" based on any of this. They did not.12 His statements were never an issue in either trial.

Nevertheless, the prosecutors, recognizing their obligation to ensure that Arete's claims were fully explored, requested permission from the Colombian government to have two agents (not one as the Report suggests) -- a DEA agent and an ATF agent -- interview Arete in an effort to verify the defendant's claim that Arete and Arete alone was responsible for the bombing of the Avianca plane. After the initial refusal by the Colombian Attorney General to allow the U.S. government agents an opportunity to interview the witness and several weeks of communication and negotiations between the State Department, the Department of Justice and the Colombian Ambassador, the two agents were granted permission to speak to Arete under certain strict limitations. During the interview, Arete told ATF Agent J.J. Ballasteros, an explosives expert stationed in Colombia and familiar with the types and nature of explosives available and utilized by the Cartels, that the explosive used to bomb the plane consisted of "gelatina" which was carried on board the plane in a black nylon bag. Arete further stated that this was "the kind used to bomb the DAS installation." (See Notes of Interview by J.J Ballasteros ("Ballasteros Notes")).

From his experience and based on his expertise with the Medellin Cartel, Agent Ballasteros opined that in 1989, the type of dynamite described by Arete as "gelatina" would have most likely been "commercial dynamite made in Colombia, Ecuador or Peru which are [sic] predominately comprised of ammonium nitrate and nitroglycerine to a lesser degree." (Ballasteros Notes). As noted above, this type of dynamite, although inconsistent with the chemical residues found in the Avianca wreckage, was commonly used by Munoz Mosquera and the Medellin Cartel. Agent Ballasteros raised some concerns regarding the method described by Arete in carrying the bomb through the airport and onto the aircraft by an "unwitting," and


12In fact, as noted above, defense counsel had possession of Arete's claims regarding the use of dynamite on Avianca long before Agent Hahn testified. They clearly could have used this information to cross-examine Agent Hahn. They chose not to.


questioned whether the bag as described "would have been greasy from the explosive material permeating through the nylon."

However, the government had no real need to "discredit" Arete13 because: (1) he never testified, and (2) apart from the questions raised by Agent Ballasteros, there were other problems with the relevant portions of Arete's statements. They were flatly contradicted by established facts and by sworn testimony of other individuals who, unlike Arete, had testified under oath subject to penalties of perjury. Specifically, Arete stated that only he and one other individual had known about or been involved in the bombing. Yet the prosecution had several witnesses who testified to the contrary. One testified that he advised Escobar as to the placement of the bomb and another admitted to his role and that of his uncle in actually transporting a portion of the bomb to Bogota from Medellin. (See Tr. 2479-84, 2659-66, 3048, 4190-93, 4403-05). Thus, apart from the fact that Arete's statement regarding the use of dynamite might actually have strengthened the government's case, the prosecution possessed specific evidence to demonstrate the falsity of those of Arete's statements that were relevant and, in fact, never needed evidence to "'discredit' the Confessor's story" since his statements were never placed before the jury. (Report at 4). However, because we felt it was not appropriate, Agent Hahn was not informed of the details of the information provided by the cooperating witnesses14 and thus, may not have been aware of the existing evidence contradicting Arete's statements.


13Prior to learning of Arete's statements, the government had detailed and specific evidence linking Arete to Munoz Mosquera's activities and the bombing of the plane. Several witnesses ultimately testified that Arete and Munoz Mosquera acted together not only to bomb Avianca but to engage in numerous other terrorist activities. (Tr. 4403-4407, 4412). To the extent that Arete's statements raised an issue, it was limited to his claim that he acted alone in bombing Avianca -- a claim clearly false as demonstrated by the other evidence in the case.

14It would, in our view, have been improper to provide Agent Hahn with the statements of the cooperating witnesses, for fear that we would have been accused of coaching our witnesses so that their stories were consistent.


C. The Significance of the Whitehurst Memorandum

With respect to the Whitehurst Memorandum, again the Report omits critical facts previously conveyed to the interviewers and misstates certain facts. First, while former AUSA Pollak was irritated over the Whitehurst Memorandum, her concerns had nothing whatsoever to do with the opinions stated regarding the chemical analysis or the issues raised by Whitehurst relative to the dynamite. Indeed, contrary to the statement in the Report that "Pollack [sic] dismissed the concerns raised in the memorandum because Bender, not Whitehurst, had actually done the analysis," AUSA Pollak had no idea who either Bender or Whitehurst was at the time she first received the Whitehurst Memorandum. Rather, she dismissed the Whitehurst conclusions for the reasons stated above: they were irrelevant both to the government's case and to the defense. Her specific concern with the Whitehurst Memorandum was the format of the memorandum and specifically, the fact that Whitehurst had listed a series of questions which seemed designed as questions for the cross-examination of Agent Hahn relating, inter alia to potential contamination, etc. Although the government is clearly under an obligation to disclose Brady material,15 there is no requirement that the government prepare cross-examination questions for the defense to use in its case, and indeed, Judge Pollak has never seen another FBI memorandum where such a format has been used. It was clear from the face of the Memorandum that Whitehurst's questions were based on sheer speculation, that he had no facts to suggest that contamination had occurred and, indeed, the prosecutors were satisfied after interviewing the two agents involved in the collection of the evidence that there was no reason for concern.

D. Agent Hahn Was a Summary Witness

Apart from the fact that certain of the Report's conclusions are flawed because Agent Hahn's testimony was analyzed out of context and without the benefit of reviewing the trial


15The Report correctly notes that Judge Pollak did not believe the Whitehurst Memorandum constituted Brady material, but fails to mention that both Judge Pollak and Ms. Wilkinson believe that the Memorandum was in fact turned over to the defense during the course of the trial even though there is no document to confirm that disclosure.


testimony of other witnesses, the Report also fails to recognize that Agent Hahn was presented in large measure as a summary witness. His testimony was preceded by that of numerous witnesses, including other experts, who testified about the planning of the bombing, the accident scene itself, the state of the wreckage, the state of the bodies recovered from the wreckage and the investigation conducted of the incident. (See, e.g., Testimony of Luis Eduardo Munoz Espitia, head of security for the Colombian Civil Aeronautics Board at Tr. 2955-2985; and Dr. Pedro Morales, forensic pathologist at Tr. 2860-2866). Indeed, as several witnesses made clear in their testimony to the jury, everyone involved, including not only the NTSB, the FAA and the FBI, but the numerous Colombian experts involved in the investigation, met on a daily basis to compare notes, share information and jointly reach conclusions regarding the incident. (Tr. 2365, 2367-68; 2971-73). Prior to Agent Hahn's testimony, witnesses had already testified about the respective roles played by the FBI, NTSB, FAA and various Colombian members of the Task Force, as well as explaining fully to the jury the fact that the conclusions reached were the product of joint efforts and the sharing of joint expertise. Thus, to suggest that somehow Agent Hahn's inadvertent use of the word "I" instead of "we" in two spots during the second trial was somehow misleading to the jury and suggested a claim of greater expertise than Hahn was qualified for takes Agent Hahn's testimony out of context and implies that the jury was unaware of the input of other experts supporting Agent Hahn's conclusions. (See Report at 22).

For example, several witnesses testified regarding the nature of the investigation, the configuration of the plane and the autopsies conducted on the bodies of the victims. Many of these were Colombians, experts in their own right with hands-on experience in the investigation. Included among these witnesses was Luis Eduardo Munoz Espitia -- from the Colombian equivalent of the FAA -- and the Colombian coroner, responsible for conducting the autopsies on numerous victims of the crash itself.

Luis Eduardo Munoz Espitia, from the Colombian Civil Aeronautics Board, testified regarding his preparation of a detailed diagram of the crash scene and the numerous photographs taken of the damage to the plane. (Report at 26). He testified extensively about touring the scene of the wreckage with Agent Hahn, and identified a photograph taken of the two of them examining certain wreckage. He also testified based on his experience and expertise about


various parts of the airplane as they appeared in the photographs. In order to maintain clarity of the record and to ensure that the jury understood what the various parts of the plane were when referred to by Agent Hahn in his testimony, the same terms were used and in part the same testimony was repeated by Agent Hahn and by Espitia. Because of the context in which Agent Hahn testified, however, we felt it was unnecessary and cumulative for him to qualify each and every statement that he made with regard to the identification of the pieces of wreckage and the function and location on the plane when it was abundantly clear to the jury that he was summarizing evidence also testified to by Espitia and other witnesses. Given Espitia's testimony, we feel that the Report unfairly criticizes Agent Hahn's description of the structure of the aircraft based on the diagrams and other photographs.

Similarly, the Report criticizes Agent Hahn for "testify[ing] to a distinct demarcation line between his duties on the one hand, and the duties of the NTSB and FAA representatives, on the other, by saying that his assignment was to determine whether an explosive device functioned on the aircraft and the duties of the others was to determine whether the crash resulted from a mechanical failure." (See page 27 of the Report, subsection g). Not only does the Report ignore the fact that other witnesses had previously testified regarding Agent Hahn's role and that of the other agencies involved, but the Report misstates Agent Hahn's testimony. Agent Hahn was first asked what his "specific assignment" was, to which he responded: "my assignment here was to go through the wreckage and try to determine whether or not, perhaps, an explosive device had functioned in this aircraft." (Tr. at 2892). He was then asked: "How did your assignment differ from the assignment or duties of the individuals from the [NTSB] and the FAA?" His response, which was specifically directed to explaining the difference between his role and theirs was as follows:

Their duties were primarily geared toward, again inspection of
records to make sure the aircraft had been properly maintained;
inspection of the flight data recorder, listening to the voice data
recorder to try to determine if there was a failure -- mechanical
failure of the aircraft for one reason or another that caused this

(Tr. at 2892-3) (emphasis added). Even without considering the context in which the jury heard


this testimony and all the evidence that had gone before, Agent Hahn nowhere drew a "distinct line of demarcation," or suggested that the NTSB or FAA had no role in investigating the existence of an explosive device, but rather through the use of the qualifier "primarily" made it clear that the enumerated duties which they performed were not exclusive but were within areas of expertise and responsibilities beyond the ones that he possessed.

Finally, the Report also criticizes Agent Hahn for including in his testimony the fact that he participated in the investigation of the Pan Am 103 accident and the World Trade Center bombing because his role in these cases was limited to examining the personal effects of the victims and managing the crime scene. Surely the Report is not suggesting that it was improper for him to testify regarding these other investigations, his observations of the scenes and his examination of the effects of the explosions there. These observations and experiences clearly became a part of his overall experience and are clearly relevant and admissible as background under existing case law. See, e.g., In re "Agent Orange" Product Liabilitv Litigation, 611 F. Supp. 1223, 1241 (E.D.N.Y. 1985) (Weinstein J.) (noting that "Rule 702 of the Federal Rules of Evidence provides for opinion testimony by experts 'if scientific, technical or other specialized knowledge will assist the trier of fact to determine a fact in issue' and the witness is 'qualified as an expert by knowledge, experience, training, or education' .... doubts should be resolved in favor of admissibility") (emphasis supplied).

Similarly, the case law is clear that experts are allowed to rely on facts or data made known to them by others, id. at 1242; Fed. R. Evid. 703, including hearsay reasonably relied upon by other experts in the field, id. at 1244-46, and to extrapolate and draw conclusions from prior experience even if they haven't had professional scientific training or conducted specific scientific study and research into a particular problem. (See Report at 11-12). See e.g. Fox v. Dannenberg, 906 F.2d 1253, 1255 (8th Cir. 1990) (discussing the fact that Rule 702 "'does not rank academic training over demonstrated practical experience"') (quoting from Circle J. Dairy. Inc. v. A.O. Smith Harverston Products. Inc. 790 F.2d 694,700 (9th Cir. 1986)). See also Loudermill v. Dow Chemical, Co.. 863 F.2d 566, 570 (8th Cir. 1988) (holding witness competent to testify as expert as to cause of plaintiff's cirrhosis even though not a medical doctor); Southern Cement Co. v. Sproul. 378 F.2d 48 (5th Cir. 1967) holding that "[a]s a general


rule,'(a) person may become qualified as an expert by practical experience.... Professional education is not a prerequisite"') (quoting Santana Marine Service, Inc. v. McHale, 346 F.2d 147, 148 (5th Cir. 1965).

The decision as to whether and to what extent a witness should be allowed to testify and give opinions is left to the discretion of the trial judge. In re "Agent Orange" Product Liability Litigation, 611 F. Supp. at 1242. In this case, Judge Johnson, the district court judge who presided over both trials was not only fully aware of the qualifications and testimony of Agent Hahn, but had heard the testimony of all of the other experts and witnesses and was fully aware of the defense case and the claims of Arete. In exercising his discretion to admit Agent Hahn's testimony, he considered all of these factors -- including many of the issues overlooked by this Report, most importantly, the lack of any controversy surrounding the issues to which Agent Hahn's testimony related.

In large measure, the Report unfairly criticizes Agent Hahn for any lack of specificity in his testimony. Apart from ignoring the context in which he testified, the Report fails to recognize that the prosecutors, being aware from conversations with the defense that Hahn's conclusions and opinions were not being challenged, and being cognizant of the criticism leveled at the government for the length of the trial and the cumulative nature of the testimony being elicited, made the deliberate decision to narrow Agent Hahn's testimony. As noted above, his testimony and that of the other witnesses made it clear that the conclusions reached by the Colombian investigators and all of the other team members were part of the information available to Agent Hahn in providing what was in essence his summary of all of the information that he garnered from all of the experts marshaled to investigate this incident and that it was all of this information that he used in forming his opinions.

E. The Report Fails to Define Terms and To Explain
Its Findings In Light of Other Experts' Opinions

The Report criticizes Agent Hahn's conclusion regarding the existence of a fuel-air explosion or flash fire, stating that the injuries experienced by the bodies "on the plane are not consistent with a flash fire or fuel-air explosion, which are of short duration." As noted above,


the findings of the coroner and the Colombian physicians who actually examined the corpses "reported damages to portions of the body relating to sudden burns, including the skin on the legs and hands which were rigid in their normal shape from the onset of the burns, albeit lacking their internal tissue." (Colombian Report at 48).16 This was entirely consistent with Agent Hahn's opinion. However, the Report concludes: "rather, the injuries indicate that the bodies were subjected to substantial heat for a significant period of time." (Report at 24) (emphasis added). The Report further suggests that it was more accurate to conclude that there was "a hot fire burning for a continuous period of time which could have led to a fuel-air explosion." Id.)17

We are troubled by this conclusion for a number of reasons. First, it flatly contradicts the conclusions reached not only by Agent Hahn, but by Walter Korsgaard and Calvin Walbert, the two experts from the FAA who were in Colombia and actually investigated the crash scene.18 Similarly, the report issued by the Colombian government and its cadre of experts who were present and directed the investigation concluded that a fuel-air explosion had occurred. 19


16(See Administrative Department of Civil Aeronautics Air Safety Division, Report of Aviation Accident, dated December 28, 1989 ("Colombian Report").

17This sentence on page 24 of the Report seems to suggest that there may have been a fuel-air explosion as a result of a hot fire, while in subsection E of Part Five (page 10), the conclusion seems to be that Agent Hahn "testified incorrectly ...concerning a fuel-air explosion." This seeming contradiction in the Report itself needs clarification.

18In several places in the Korsgaard Report, Korsgaard presents his opinion that a fuel-air explosion occurred (Korsgaard Report at 4, 5) and indeed, notes that "[t]he APU located at the rear of center fuselage wing box section is blown to [the] rear of aircraft by the force of the fuel-air explosion within this center section fuell tank" Id. at 5). He also observes that the "evidence indicated severe burning in the area below the cabin floor and damage typical of flash over in the passenger cabin area (Id. at 1) (emphasis added). During an interview conducted prior to the first trial, Korsgaard's partner, Calvin K. Walbert, also with the FAA, independently confirmed Korsgaard's opinion that a "fuel-air explosion" had occurred.

19The Colombian Report concluded "after a careful examination of the bodies, their injuries and their types of burns, the finding is that there was an explosion inside the aircraft in mid-air, which was subsequently aggravated by the explosion of some type of gas (oxygen, fuel fumes or other substance)." (Colombian Report at 39) (See also pp. 44 of the Colombian Report, discussing the "fuel-air explosion" and p. 51 in the section labeled "Findings," where the report concludes that "an explosive device which used a relatively small amount of high power


It is not clear from the Report whether the experts reviewing Agent Hahn's testimony were given access to these other reports (copies of which are available upon request) or whether they ever discussed their analysis with any of these other experts who were actually present, saw the fire and structural damage first-hand, and spoke on a daily basis with all of the Colombian experts involved in the case. Indeed, one of the problems with evaluating and commenting on this section of the Report is that the Report fails to set forth the scientific or other foundation on which it bases its conclusion that there was no fuel-air explosion or "flash fire."

Moreover, the Report suffers from some of the same problems that it identifies in Agent Hahn's testimony. It fails not only to specify the basis for its conclusions, but it fails to define terms. For example, the Report concludes that the fire burned for "a significant period of time" or a "continuous period of time." (Report 24). What does that mean? Clearly, had the drafters of the Report reviewed all of the evidence, they would have realized that the bodies were subjected to fire for only a matter of a minute or two, possibly only seconds, between the time of the first explosion and the second explosion which blew the plane apart and brought it to the ground. As a review of the recordings on the black box showed, the plane was cleared for take-off from Bogota at 7:11:48 a.m., and travelled less than 6 minutes20 before the crash occurred. The flight recorder data, which terminated at the time of the first explosion, showed that the plane had only reached an altitude of approximately 13,000 feet when the first explosion occurred. According to the eyewitness reports, the eyewitnesses heard the first explosion, observed fire emanating from the right side of the plane in the vicinity of the wing, and "after several seconds" observed a second explosion which blew the plane apart and brought it crashing to the ground. (Tr. at 2983). The voice data recorder and technical data recordings show that prior to the first explosion at 7:13 a.m., everything was fine on board the plane; there was no evidence of any fire, excessive heat or other problem prior to that time.


explosives was detonated....and that [it is likely that a fuel-air explosion caused by hot gases might have occurred shortly thereafter, causing the aircraft to break apart").

20 The Colombian Report states the time of the crash as 7:16:39 local time. (Colombian Report at 1). The Korsgaard Report notes the time of the crash as "[a]bout 0717 (local time)." Korsgaard Report at 6).


Thus, common sense tells us that at most, the people on the plane were subject to a "hot fire burning" or "substantial heat" for no more than two to three minutes. Indeed, given the eyewitnesses' accounts, it was probably even less time. If this is what the Report means by "a significant period of time" or "a continuous period of time," then it should so state. Otherwise, the Report's conclusions in this regard are not only misleading but appear to ignore all of the objective evidence in the case.


In summary, while we recognize the difficulties inherent in evaluating an expert's testimony in the context of a trial of several months duration, here there are some serious misconceptions upon which the Report is based that, in the end, has produced the erroneous conclusion which appears twice in the Report --namely, that any errors committed by Agent Hahn "tended to help the prosecution's case or rebut a defense." Report at 39; see also Part Five, subsection E at 10). Since it is obvious that the writers of the Report may not have had access to or did not recognize the significance of the other evidence, it is understandable how they could have reached the conclusion that Agent Whitehurst's questions regarding the possible use of dynamite were harmful to the prosecution's case and Agent Hahn's testimony was helpful to the prosecution. Nevertheless, we would suggest that the Report be clarified to reflect the true nature of the prosecution's case and the fact that at best Agent Whitehurst's testimony was irrelevant and at worst, the prosecution failed to present a stronger case for conviction than we did. Furthermore, we think that the Report should make clear whether it disagrees with Agent Hahn's ultimate opinion that there was an explosive device that functioned on board the plane, breaking the plane in pieces and resulting ultimately in the deaths of the passengers and crew members on board. Since this conclusion was the only issue even arguably relevant to the case, the Report's position and its basis for reaching that conclusion should be stated.

Magistrate Judge Pollak has reviewed the trial transcripts and the various reports prepared by the other experts in this case, and discussed the Report and this letter with both Beth Wilkinson, Special Attorney to the United States Attorney General, and Special Agent Trotman, case agent on the Munoz Mosquera prosecution. They would all be more than happy to speak to


anyone regarding this issue and to supply whatever additional materials or testimony may be required to understand or clarify the questions raised herein. Please do not hesitate to call Judge Pollak at (718) 260-2360, Ms. Wilkinson at (303) 313-2299 or Agent Trotman at (609) 757-5407.

Respectfully submitted,


Zachary W. Carter
United States Attorney
Eastern District of New York



United States Magistrate Judge
ROOM 208

March 7, 1997


Barry Elden, Esq.
Special Investigative Counsel
United States Attorney's Office
219 Dearborn Street
Room 500
Chicago, IL 60604

Dear Mr. Elden:

Pursuant to our telephone conversation of February 26, 1997, I have copied those portions of certain transcripts which I think exemplify the way Special Agent Hahn's testimony appeared to the jury in context with the other witnesses who testified.

Specifically, I have included the transcripts of those witnesses who testified regarding the Avianca plane, such as Luis Eduardo Munoz Espitia and Dr. Morales, both of whom are mentioned in the earlier letter submitted by U.S. Attorney Zachary Carter. I have also included portions of the testimony of Special Agent Dwight Dennett who testified not only about the plane investigation, but also about the DAS bombing and certain rocket attacks against the U.S. Embassy. If you review, in particular, Mr. Munoz Espitia's testimony at pages 2956, 2963-2968, 2971-2974 and Agent Dennett's testimony at pages 2363-2368, 2370, 2372-2375, you will see that they both discuss, as does Agent Hahn, the nature of the investigative team formed, the members of the team, as well as the general procedures and methodology followed during the Avianca investigation.

I have also enclosed, per your request, the Colombian Report in Spanish and translated into English, as well as the Koorsgaard Report, in case you need a copy. Please let me know if there are any other transcripts or reports that you would like to see.


One thing you should understand, however, is that these witnesses were not the only expert or technical witnesses who testified in the case. As an example, I have also included the testimony of Detective Francisco Fonseca, who testified about the DAS bombing and Captain Pena, the Colombian bomb squad expert, who testified about the Avianca and Maza truck bombings.1 In addition to the five witnesses whose transcripts I have provided, there were several other technical expert witnesses, including Special Agent Jordan from the FBI laboratory and several Colombian military and police officers, who testified relating to several of the other bombing/rocket incidents with which Munoz Mosquera was charged as part of the conspiracy in this case. Overall, even after deliberately eliminating a number of witnesses who had testified in the first trial, the government presented the jury in the second trial with over two and a half weeks of technical/expert testimony describing the methodology used by the defendant and his co-conspirators to perpetrate the acts charged. By the time the presentation of expert/technical evidence was completed, the jury had been saturated with technical terms and expert testimony -- none of which was critical to the case in that it did not relate to issues in dispute. Instead, as explained in Mr. Carter's earlier letter, this evidence was in essence background information for all of the incidents, presented to the jury to enhance their understanding, but not critical to establishing essential elements of the offenses charged.

We, as prosecutors, made the decision to have several witnesses, such as Agent Hahn, summarize for the jury the nature of the investigation of each act and the technical conclusions reached as a result of the investigation rather than have each individual who participated in each investigation testify about their particular findings in their area of expertise. In part, this was fueled by the extreme reluctance of certain of the Colombian witnesses to testify at all regarding the incidents for fear of retaliation by Munoz Mosquera's brothers, also terrorists and assassins for the Cartel. The decision was also influenced by a sense, gathered from the experience of the first trial, that there were too many witnesses, the trial was taking too long, and the key information -- in fact the only relevant information to the issue in controversy, namely, did


1I have included these witnesses as extra examples because they, like Agent Hahn, also testified about the DAS and Avianca bombings.


Munoz Mosquera participate in these acts -- was to be derived from the testimony of the cooperating witnesses. Thus, while we could have called Walter Koorsgaard and Calvin Walbert to testify, or the individuals from Pratt and Whitney, we decided, based on the issues in controversy in the case to limit the number of witnesses and shorten the testimony on those areas where the defense had already conceded there was no dispute.

In retrospect, given that Agent Hahn's testimony was not critical to establishing the essential elements of the offenses charged, we might seriously have considered not calling Agent Hahn at all to present his summary testimony, simply to spare him the problems caused by this investigation. It is my position, based on the purpose and nature of his testimony, the decisions we made as prosecutors, and the fact that what he has been criticized for was simply not relevant to the issue in controversy, that he has been unfairly attacked.

I apologize for the time it has taken to put this information together for you, but as I indicated on the phone, I am currently trying a two-week medical malpractice case which is occupying most of my time right now. However, if you have any questions, please don't hesitate to call me and I'll try to return your call during a break or after trial. I am happy to assist you in any way that I can. Thank you for your consideration of this material and I hope my letter is of some assistance in responding to your questions.

Cheryl L. Pollak


cc: Michael Bromwich
U.S. Department of Justice
Room 4706
10th and Constitution Avenue, N.W.
Washington, D.C. 20530