The Friction Ridge
Written by Michele Triplett   

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Recommendations on how to avoid testimony errors

FORENSIC PRACTITIONERS are commonly asked to testify in court, yet they may have limited knowledge regarding the rules of testimony. This lack of understanding could unintentionally affect the outcome of a trial. Awareness of a few simple concepts could improve your testimony and prevent a mistrial or reversal of a court decision.

Recommendation #1:
Avoid testifying to the conclusions of others

Testifying to the conclusions of others is detailed in three United States Supreme Court Decisions. Crawford v. Washington (2004) states that under the Sixth Amendment Confrontation Clause, “the accused shall enjoy the right…to be confronted with the witnesses against him,” with an exception allowed for business records. The exception to the Crawford rule resulted in many forensic laboratories considering their reports “business records” and therefore not participating in live testimony.

Melendez-Diaz v. Massachusetts (2009) clarifies the acceptability of forensic reports as business records stating, “The analysts’ certificates—like police reports generated by law enforcement officials—do not qualify as business or public records…”

Bullcoming v. New Mexico (2011) clarifies the Confrontation Clause even further by stating who shall be permitted to give the testimony. “The question presented is whether the Confrontation Clause permits the prosecution to introduce a forensic laboratory report containing a testimonial certification—made for the purpose of proving a particular fact—through the in-court testimony of a scientist who did not sign the certification or perform or observe the test reported in the certification. We hold that surrogate testimony of that order does not meet the constitutional requirement.”

These three decisions clearly specify that a forensic analyst who performed the examination must provide the testimony.

An analyst testifying to the results of the reviewer or verifier is a similar type of error since the analyst did not perform these tasks. Past cases have labeled this as inadmissible hearsay and/or falsely bolstering the primary analyst’s conclusion. If an attorney objects to this type of testimony, then the courts must decide if the error was harmful to the case and if a mistrial or reversal is warranted. Whether or not an error is harmful is specific to each case.

Recommendation #2:
Prepare to provide the basis underlying a conclusion

Analysts are required to provide the basis underlying their conclusions if requested. If an analyst has never been asked for the basis underlying past conclusions, they may not be aware of the requirement to provide this information. Federal Rules of Evidence Rule 705 describes “Disclosure of Facts or Data Underlying Expert Opinion”. This rule states: “The expert may testify in terms of opinion or inference and give reasons therefore without first testifying to the underlying facts or data, unless the court requires otherwise. The expert may in any event be required to disclose the underlying facts or data on cross-examination.”

In order to give more weight to a conclusion, a prosecutor may request demonstrable materials themselves prior to cross-examination. Chart enlargements or PowerPoint presentations can be simple methods of providing the basis for comparative evidence conclusions during testimony.

Recommendation #3:
Avoid reference to past criminal history

Testifying to a defendant’s past criminal history could be prejudicial toward the guilt of a defendant. Any reference to a prior criminal history should be avoided, such as testifying that a latent print was matched to a fingerprint card on file from a previous arrest.

Recommendation #4:
Disclose exculpatory information

Analysts should be aware of Brady v. Maryland (1963), Giglio v. United States (1972), and United States v. Henthorn (1991). These rulings require government witnesses to disclose exculpatory information to the defense (information that may assist in clearing a defendant). Exculpatory information may include disclosing all conclusions—not simply conclusions that implicate the defendant; disclosing information about anyone who may have disagreed with the reported conclusion; and disclosing unfavorable information about the analyst. This information is explained further in “Brady Material and the Expert Witness,” Evidence Technology Magazine, January-February 2011 (Page 10).

Recommendation #5:
Avoid overstating conclusions

Federal Rules of Evidence Rule 702 describes “Testimony by Experts”, stating: “If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by know-ledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise, if (1) the testimony is based upon sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case.”

Since expert testimony is commonly referred to as opinion evidence, some could incorrectly assume that conclusions may be the personal opinion of the expert. An important element of Rule 702 is that conclusions must be based on sufficient facts or data. Testifying to a conclusion that is merely the personal belief of the expert—not based on sufficient facts or data—may be overstating a conclusion and would therefore be considered an error in testimony.

Many examples can be shown where testimony errors have occurred but not had any negative effect on the outcome of a case, falsely implying certain testimony is permissible. Minor errors may be tolerated if there is no objection to the error or if the error is considered harmless.

Nevertheless, forensic practitioners should be aware of testimony rules to avoid testifying incorrectly themselves and adversely affecting the outcome of a trial.

About the Author

This e-mail address is being protected from spam bots, you need JavaScript enabled to view it is Latent Operations Manager of the King County Sheriff’s Office in Seattle, Washington. She holds a Bachelor of Science degree in Mathematics and Statistical Analysis from Washington State University and has been employed in the friction-ridge identification discipline for more than 19 years.

 
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