The Expert Witness Controversy - Essay Example

One of the initial problems with expert testimony is that it is used by both the prosecution and the defense. The two experts must necessarily be at opposition in an effort to help their side's case and one of them must be wrong. This is further complicated by the vast number of "Expert Testimony Services" that have cropped up in recent years as lawyers and investigators pursue an expert-for-hire strategy. Some of these firms have been criticized for advertising that they will be paid only if they win the case.

This is contrary to science and removes the neutrality of the scientific method. This attitude extends itself into the prosecution as government and police labs exaggerate claims or suppress evidence. In the case of Bromgard vs. Montana, Jimmy Ray Bromgard was convicted of raping an 8 year old girl based on a forensics expert who testified that the hair found at the scene had only a 1 in 10000 chance of not being Bromgard's. This expert testimony was fraudulent as there were no means to statistically match hairs through microscopic inspection.

Another problem with expert testimony enters the courtroom by way of new technology that may be unproven and unreliable. Termed "junk science", it is sometimes used by the defense to instill reasonable doubt, and more often by the prosecution to sway a jury in their favor. The 1993 case of Daubert vs. Merrill Dow Pharmaceutical set strict guidelines that lower courts must use to determine the admissibility of scientific evidence. It mandated that expert testimony be proven valid, reliable, peer reviewed, and generally accepted by the scientific community (Junk science, 2005).

However, as new technology arises, it finds its way into court cases and is only upheld or overturned after years of appeal. When first introduced, fingerprint enhancement was labeled by defense attorneys as ".junk science, unreliable, and easily manipulated" (DeMarzo, 2003). Though the appeals process eventually upheld this technique, it runs the risk of alienating a jury and may result in a guilty verdict being overturned on appeal. The American Medical Association has been proactive in protecting the credibility of its profession by setting standards for medical testimony.

In 1998 they adopted a policy that states, ". expert witness testimony is the practice of medicine subject to peer review" (Reardon, 1998). Medical malpractice suits and the questionable ethics of a Doctor receiving a contingency fee upon winning the case should arouse a sense of trouble in all involved. Expert testimony as it pertains to psychiatry is equally as troublesome as was seen in the case of John Hinkly. More recently, the case of Andrea Yates was overturned and ordered a new trial because of inaccurate testimony given by a leading forensic psychiatrist for the prosecution (Hausman, 2005).

Further complicating the case was the controversial "Postpartum