Can Forensic Experts Overcome their Cognative Biases?

Is Recognizing Cognitive Biases Enough?

Black’s Law Dictionary defines bias as, “[a] predisposition to decide a cause or an issue in a certain way (Garner, 2009).”  Prior experiences, learning paradigms, individual beliefs, and other biases can cloud the understanding of what is important.  There are two types of biases: cognitive bias and motivational bias (Giannelli, 2008).  Cognitive bias occurs at the subconscious level and frequently interfere with the ability of people to make good decisions.  Motivational bias can occur at the conscious or subconscious level and result from a person’s desire to deliver expected results.

Black’s Law Dictionary offers four types of courtroom bias.

  1. Actual bias occurs when “[g]enuine prejudice that a judge, juror, witness, or other person has against some person or relevant subject” is present.  Examples of this bias are when a person believes a member of an ethnic or racial group possess certain behavioral traits.  Actual bias may cause a trier of fact to believe or not believe a person committed a certain act. Actual bias may be induced as cognitive bias when a testifying expert or jury is given information about the case that is not pertinent to the expert’s scope of work. An example is offering information that a suspect has previously been convicted of an offense similar to the one currently being adjudicated.
  2. Advocate’s bias is present when an advocate for a person or cause becomes too involved with the person or cause being advocated.  As an attorney, your job is to advocate for your client’s case, whether or not you believe the client is guilty of the charges or claims.  The retained expert is an advocate for the evidence rather than for a party to the case.  The expert must take care not to allow cognitive bias to influence an opinion. When an attorney becomes too involved with a case, advocate’s bias may develop, causing the attorney to make mistakes and overlook important issues.
  3. Implied bias can result from relationships among parties.  The expert witness must avoid any implied bias by receiving full payment for services ahead of offering testimony.  The implied bias is that the expert is testifying in a particular manner to ensure receipt of payment.  Another form of implied bias is if the expert has a relationship with a party to the case.
  4. Judicial bias occurs when the judge or trier of fact has a bias in favor of one of the parties in a case.  Judicial bias may take the form of the other forms of cognitive bias where the judge is not consciously aware of the bias.

By applying analytical methods developed through training, education, and practice, experts develop opinions as to the interpretation of the examination of the evidence.  Prior experience may induce biases that cause the expert to use trusted methods without considering alternatives of investigation.  Forensic science seeks to produce reliable evidence which is clearly reported (Sjerps and Meester, 2009).  Experts must recognize when their biases and those of others influence their decisions.

Examples of Courtroom Bias

Length: 7:39
This is a portion of a presentation delivered by forensic document examiner, Mike Wakshull, to the Forensic Expert Witness Association‘s conference in San Diego. The title is “Will Courtroom Bias Cost You Your Next Case?” The audience was practicing forensic experts across many disciplines.

Courtroom Bias Overview

Length: 16:31
This video is the beginning of a presentation on the topic of courtroom bias to the Association of Legal Nurse Consultants of San Diego by forensic document examiner Mike Wakshull. The video introduces the topics of advocate’s bias, juror’s bias, and judicial bias as defined in Black’s Law Dictionary ninth edition.

The effects of Expert’s Bias

This presentation was delivered by Mike Wakshull, forensic document examiner, to the annual conference of Scientific Association of Forensic Examiners. Mike describes how cognitive bias adversely affected one of his cases. Aspects of recognizing cognitive bias are presented for forensic experts.