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Expert Testimony and the Potential for Its Abuse

Below is my research paper for my Criminal Evidence class. Reminder: this paper is in Turnitin so if you plagerize it, you will be caught. There are some really good sources, so use those when doing your own research. Comments always welcome!


Expert Testimony and the Potential for Its Abuse

Reagen Dandridge Desilets

Trident Technical College

CRJ236 Criminal Evidence (W04)

November 25, 2014


Many people rely on expert testimony to help clear up parts of criminal cases that the average lay person may not understand. Psychologists, forensics scientists, and physicians are all commonly seen as expert witnesses in trials where a combination of extensive education and experience qualifies their testimony. Other expert witnesses may include those in fields such as mechanics, accountants, or other trade specialties where experience alone qualifies them. While the need for experts at a trial can be vital, there have been problems both with what qualifies as “expert” as well as testimony offered by some experts. This paper will look at a few cases to show examples of these problems, what has been done in the past to try and counter these problems, and suggest some more ways to mitigate or eliminate such risks.

Expert Testimony and the Potential for Its Abuse

Lord Mansfield said, “The opinion of scientific men upon proven facts may be given by men of science within their own science,” in reply to an objection during the 1782 Folkes v. Chadd case in the United Kingdom (Rix, 1999). This is traditionally accepted as the first case where expert testimony was offered in a trial when engineer Thomas Smeaton testified regarding harbor decay and the demolition of a sea-bank. For more than two centuries, expert testimony would grow and evolve. Today, the Federal Rules of Evidence Article VII sets the tone for what is acceptable as expert testimony in the United Sates; however, it is a wide set of parameters and there is some room for interpretation (Legal Information Institute, 2014).

Federal Rule 702 states that an expert is anyone with the “knowledge, skill, experience, training, or education” in their field, and they can state their opinion in regards to their field related to the testimony (Legal Information Institute, 2014). It also states that the testimony must meet certain criteria to be considered as expert testimony and should be as follows:

  • the expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue;
  • the testimony is based on sufficient facts or data;
  • the testimony is the product of reliable principles and methods; and
  • the expert has reliably applied the principles and methods of the case.

Further amendments were made in subsequent cases, such as Daubert and Kumho, to charge judges with making sure that all expert testimony, scientific or otherwise, is reliable. The reason for these safeguards was to help lessen the risks of abuse of expert testimony in trials to unfairly sway a jury in favor of one side or another, either prosecution or defense.

However, there are times when bad experts and bad testimony gets into a trial, despite the safeguards put in place. Even in recent times, there have been cases where the dubious qualifications of an expert were called into question, but still the expert was allowed to testify. There have also been experts that are well qualified but the testimony itself had problems. It is vital that such situations be carefully vetted to avoid miscarriages of justice.

An example of problematic expert qualifications can be seen in the 1994 case of teenagers Damien Echols and Jason Baldwin, more famously known as the case of the West Memphis Three (Steel). Other problems with this case aside, the prosecution’s expert testimony on occult crimes was offered by Dale Griffis. During the process of trying to establish his credentials, the defense showed questionable education and a lack of experience in the field for which he was testifying in this case, occult crime (UMKC, 1994). The defense pointed out and got Griffis to admit that while getting his Ph.D. with Columbia Pacific University that he did not follow a prescribed set of courses. In fact he said he took no classes at all to earn his Ph.D., and instead relied on regular correspondence that tailored his educational work solely to his own needs, combining it with life experience as he was a full time working police captain while enrolled. Griffis also said that the university was not accredited, but rather “state certified”. In his dissertation, which was reviewed by a board that included his own mentor, the section on cult crimes was co-authored with a lawyer. He had four books published, some of which he used elements of his own dissertation in. There was no other training or education in the area of occult or cult crimes. Griffis had also only worked sporadically as an “occult expert” in a consultant manner, citing actual trial experience for occult testimony three times, so his experience was limited. Despite the defense showing this severe lack of education, training, and experience, the judge still considered him a qualified expert. It would further be revealed that Griffis had not conducted a thorough investigation of this specific case before testifying. He didn’t even know the names of the defendants and had only corresponded with detectives and prosecutors prior to the trial. The process of vetting this particular witness for expert testimony should have filtered him out, but it did not. The defendants were found guilty, and Jason Baldwin was sentenced to life in prison while Damien Echols was sentenced to death. Eventually, after much controversy, all parties involved would agree to Alford plea deals (Robertson, 2011). This would allow them to proclaim their innocence, but also allow the state of Arkansas to claim there was enough evidence to convict them anyway. After nearly twenty years in prison Jason Baldwin, Jessie Misskelly, Jr., and death row inmate Damien Echols were released.

Another problem that can be seen in regards to expert testimony is when the expert is well qualified, but there are problems with the opinion or facts the expert is presenting. This was evidenced in the 2002 case of Texas mother Andrea Yates when well known expert witness Dr. Park Dietz, a psychiatrist, testified for the prosecution (Colb, 2003). Dr. Dietz was not familiar with post partum mental illnesses, which Yates was said to be suffering before and during the homicides of her children she was on trial for. Yet, he declared that she was sane when she killed her children. The Yates’s defense team did everything they could to challenge the notion that she was sane (Steel). However, in his rebuttal, Dr. Dietz testified that shortly before she killed her children, there was an episode aired of Law & Order in which a character drowned her children and claimed insanity to get away with it (Park, 2008). Yates was convicted in large part due to Dr. Dietz’s testimony. It was later discovered that no such episode had ever been written. There was significant outrage when it was discovered that Dr. Dietz did not remember the information about the television show correctly. However, instead of tossing the conviction, the judge told the jurors that they could consider life in prison instead of the death penalty since they were in the sentencing phase. Eventually, her defense won an appeal and she was re-tried and found not guilty by reason of insanity.

There have to be ways implemented to help mitigate the risks of these unacceptable errors. People’s freedom, and indeed their very lives are at stake. The cause of justice must be thorough, complete, and beyond reproach. Human bias must be blinded and science has offered ways to do so.   Confirmation bias is when someone looks to find evidence or interpret evidence in such a way that it confirms their own personal beliefs and preconceived notions about a given topic, idea, or hypothesis (Nickerson, 1998). In the case of the West Memphis Three, detectives and prosecutors sought out Griffis to confirm their bias of Satanic rituals for murder simply because of the odd appearance and strange behavior of the teenagers suspected (Steel). There were claims that the evidence at the scene matched such rituals; however, much of the facts that Griffis testified to were incorrect and evidence was misrepresented to fit the Satanic narrative as opposed to allowing the evidence to tell its own story. In the Andrea Yates case, Dr. Park Dietz “misremembered” a random idea from a television show and nearly had a woman executed for it. It has even been claimed that he was a “hired gun”, working only to testify to the sanity or insanity of whichever side was paying him to say so (Tolson, 2005). This would lend credence to the bias that he had for the prosecution, offering up whatever it took to give them a winning edge in the case, if it were indeed true.

It has been suggested that there is not enough education in the area of forensic psychology when obtaining various degrees in law and criminal justice, and that may evidenced in the cases mentioned above (Goodman-Delahunty, 1997). Perhaps if there were a better survey of the topics concerning so-called “soft” sciences, such as psychology, as part of the curriculum then there would be a better understanding of what could qualify an expert in a field as obscure as occult crimes. Perhaps if a defense attorney were better trained to know what to look out for when a prosecutor’s star psychiatrist is testifying an opinion that is not based on actual facts, then false convictions could be better avoided. In physical, or “hard”, sciences, it’s a bit easier to qualify the evidence (Faigman, Monahan, & Slobogin, 2014). Is it testable and falsifiable? What are the error rates? Was it accepted and published by a peer reviewed process? All of these factors make it far easier to assist judges in the process of deciding if expert testimony and evidence is admissible during a trial. While it is more difficult to apply these questions to soft science, it is not impossible and should still always be applied.

In the case of the West Memphis Three, had anyone used those standards in qualifying Griffis’s credentials, the noted lack of legitimate education, occult investigation experience, and the lack of peer reviewed publications would have been immediate red flags (UMKC, 1994). In the 1980s and early 1990s there had been multiple occult crime scares fueled in large part due to the media (Victor, 1990). However, there was no shortage of experts working to dispel the myths and quell the fears (McRobbie, 2014). In 1992, even the FBI released a report on the topic of Satanic Ritual Abuse that largely explained reasons behind a lot of why these reports were false, misleading, or misrepresented (Lanning, 1992). There would have been several, more reliable sources available to impeach Dale Griffis as a credible witness. In the Andrea Yates case, if Dr. Dietz had to submit formal evidence of the episode in which he claimed Yates mimicked, such as a transcript of the episode, then it would have been discovered immediately to have never existed (Park, 2008). It was also known that Dr. Dietz was unfamiliar with post partum illnesses and their effects and treatments (Colb, 2003). Any hard evidence produced of his lack of experience in those illnesses would have been important to present during the trial. Combine that information with the knowledge that the show did not exist and they may have been able to successfully impeach him as a credible witness.

It is of the utmost importance to be sure that expert testimony is held to the highest standards possible. Since the jury is composed of lay people, understanding certain elements of evidence are vitally important to the process. If the qualification of witnesses is sloppy, or if the testimony offered by witnesses is careless, then the cause of justice has already been lost. Victims will not have answers or resolution and the accused will not have due process. If problems such as confirmation bias and assumptions are allowed to creep into action, then we will continue to see cases such as those given above. However, if objective and mindful procedures are the forward movements into any case, then it will greatly increase the chances of seeing the truth revealed and justice prevail.


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