A Primer on Preparing for the Prosecution’s Expert

Despite the fact that experts have always played a prominent role in both civil and criminal trials, many lawyers fail to challenge experts utilized by the prosecution. Challenges are rarely brought despite the fact that some so-called “experts” are unqualified for poorly trained. There are steps that must be take in any case when the government remains an expert. Successfully attacking a prosecution expert is a goal within the reach of any prepared trial lawyer.

10 Steps:

1) Obtain the expert’s resume or CV (Curriculum Vitae) 

Make sure everything listed is accurate. Many experts are simply qualified in the fields in which they testify. Experts exaggerate their qualifications, including their education. Some testify in areas well beyond their expertise. Many simply lie on the CV; some never attended the schools listed. Occasionally experts lie about their publications or contributed little, if anything, to the publications listed. When an expert’s resume indicates that she is board certified should the defense be impressed? Investigate the organization through which she or he claims certification. Does the organization administer a test for individuals seeking board certification? Is it a written test or an oral test? What does the test entail? Some organizations will allow anyone to become board certified in exchange for payment of a fee.

2) Examine all writings of the expert 

Experts, especially those in the academic field have written on a variety of subjects. From time to time experts forget what they wrote many years ago, or even just one or two years previously.

3) Use legal resources to locate cases in which the expert previously testified

Westlaw and Lexis will provide some of this information. The “experts database” at www.nacdl.org is a good source.

4) Obtain the expert’s past testimony and experts

Experts that faced cross-examination have probably testified in ways that they may later regret. Past testimony might indicate that they may later regret. Past testimony might indicate that the expert is in agreement with the testimony the defendant’s expert will give in the present case. If nothing else, transcripts will give defense counsel a true flavor for the way experts present themselves, and talking to the lawyers who have examined these experts will fill in the gaps.

5) Research the labs with which the experts are associated

Many labs are unaccredited or have been cited numerous times by government oversight agencies and private watchdogs. This kind of information can lead to very fertile cross-examination questions and answers.

6) Subpoena all underlying raw data upon which the experts relied, and subpoena laboratory procedure manuals.

Defense counsel’s motion for data should be specific and seek every scrap of paper, including emails and handwritten notes. Many scientists do not follow their own lab procedures; some are not aware of the procedures.

7) Conduct a one-on-one interview with the prosecution’s expert whenever possible. 

In theory, the government’s expert is neutral, but every defense attorney knows this is not true. Although government experts are biased, they will meet with defense attorneys. An interview will allow the defense attorney to assess the expert as well as the opinions the expert will provide at trial. For example, meeting with a forensic pathologist and reviewing the case with him or her can show defense counsel that the defense needs its own pathologist.

8) Expose any hidden bias on the part of the expert

Many of the prosecution’s forensic experts are obviously bias. This bias might simply result from the fact that they work so closely with law enforcement officers and prosecutors an only testify for them. The bias can result from correspondence sent by the police or prosecutors that includes prejudicial information. Of course, if the prosecution retains an independent expert, the financial arrangements involved are admissible on cross-examination.

9) Use ‘learned treaties’ in preparation for cross-examination of the government’s expert

Rule 803 (18) of the Federal Rules of Evidence,  if it is utilized correctly, has the potential to enable a defense attoney to effectively call a witness (that could cost thousands of dollars) without ever calling him to the witness stand the witness could even be dead. Previously published work that qualifies as a learned treatise can be acknowledged by the defense’s expert or the prosecution’s expert and thus be used to undercut the opposing expert’s opinion at trial. Thus, a previously published work acknowledged as a learned treatise can be utilized to impeach the testimony of the prosecution’s expert. This is particularly effective if the prosecution’s expert has testified to facts contrary to what is stated in a learned treatise authored by someone the prosecution’s expert has acknowledged as authoritative in the field. Note, however that while experts can be read to the jury during cross-examination, they cannot be admitted as substantive evidence.

10) Insist that the prosecutor follow Rule 16(a)(1) (G) of the Federal Rules of Criminal Procedure 

Sometimes prosecutors disclose limited information regarding their experts. Pursuant to Rule 16 of the Fedearl Rules of Criminal Procedure, at the defendant’s request, the government must give to the defendant’s request, the government must give to the defendant a written summary of any testimony that the government intents to use under Rules 702, 703, or 705 of the Federal Rules of Evidence during its case-in-chief at trial.

Like other witnesses, expert witnesses have weaknesses and vulnerabilities. Investigating the expert and the subject matter will provide oppurtunities not only to level the playing field, but also to gain an advantage. 

Author: Richard S. Jaffe

The Morales Law Firm would like to thank The National Association of Criminal Defense Lawyers Champion for sharing this information with us. (March 2013)