Monday, May 23, 2016

The Fickleness of Eyewitness Testimony

In 1673 Thomas Cornell (Jr.) was accused, tried, convicted and hanged for the alleged murder of his mother, Rebecca Briggs Cornell, in Portsmouth, Rhode Island. He was convicted using circumstantial evidence as well as spectral evidence, in which witnesses recounted dreams involving ghosts pointing to his alleged guilt. American jurisprudence was later modernized to exclude the use of apparitions and dreams as evidence in trials. This case and its history have been chronicled in the book Killed Strangely: The Death of Rebecca Cornell by Elaine Forman Crane.

Over three hundred and twenty five years later in 1998, Richard Alexander was convicted of a series of rapes in South Bend, Indiana and was dubbed the "River Park Rapist". He was convicted largely on the basis of eyewitness testimony. In 2001, with Alexander already having served five years in prison, an alleged burglar and child molester named Michael Murphy confessed to one of the two rapes of which Alexander had been convicted, knowing details only the true assailant would know. With this revelation, a judge ordered a new round of DNA testing in Alexander's case. Hairs found at the scene of the rape were submitted to mitochondrial DNA testing. At the time of Alexander's original conviction, such testing was not available in the State of Indiana. The tests proved that the DNA did not match Alexander's profile, but did match Murphy's. Alexander was released from prison on December 12, 2001.(*1)

Researchers have reported that 73 percent of the 239 convictions overturned through DNA testing were based on eyewitness testimony. One third of these overturned cases rested on the testimony of two or more mistaken eyewitnesses. How could so many eyewitnesses be wrong?(*2)

In addition to being used in criminal trials, eyewitness testimony is routinely utilized in civil cases ranging from automobile accidents to custody disputes. Eyewitness testimony is fickle and, all too often, shockingly inaccurate. Yet judges and jurors often uncritically accept such evidence.

Researchers have reported that (*3):

The uncritical acceptance of eyewitness accounts may stem from a popular misconception of how memory works. Many people believe that human memory works like a video recorder: the mind records events and then, on cue, plays back an exact replica of them. On the contrary, psychologists have found that memories are reconstructed rather than played back each time we recall them. The act of remembering, says eminent memory researcher and psychologist Elizabeth F. Loftus of the University of California, Irvine, is “more akin to putting puzzle pieces together than retrieving a video recording.” Even questioning by a lawyer can alter the witness’s testimony because fragments of the memory may unknowingly be combined with information provided by the questioner, leading to inaccurate recall.

Many researchers have created false memories in normal individuals; what is more, many of these subjects are certain that the memories are real. In one well-known study, Loftus and her colleague Jacqueline Pickrell gave subjects written accounts of four events, three of which they had actually experienced. The fourth story was fiction; it centered on the subject being lost in a mall or another public place when he or she was between four and six years old. A relative provided realistic details for the false story, such as a description of the mall at which the subject’s parents shopped. After reading each story, subjects were asked to write down what else they remembered about the incident or to indicate that they did not remember it at all. Remarkably about one third of the subjects reported partially or fully remembering the false event. In two follow-up interviews, 25 percent still claimed that they remembered the untrue story, a figure consistent with the findings of similar studies.

In the mid 1970’s researcher Elizabeth Loftus performed experiments demonstrating the effect of a third party introducing false facts into memory.(*4) The experiments were described as follows: (*5)

Subjects were shown a slide of a car at an intersection with either a yield sign or a stop sign. Experimenters asked participants questions, falsely introducing the term "stop sign" into the question instead of referring to the yield sign participants had actually seen. Similarly, experimenters falsely substituted the term "yield sign" in questions directed to participants who had actually seen the stop sign slide. The results indicated that subjects remembered seeing the false image. In the initial part of the experiment, subjects also viewed a slide showing a car accident. Some subjects were later asked how fast the cars were traveling when they "hit" each other, others were asked how fast the cars were traveling when they "smashed" into each other. Those subjects questioned using the word "smashed" were more likely to report having seen broken glass in the original slide. The introduction of false cues altered participants’ memories.

A number of factors can reduce the accuracy of eyewitness identifications and recollections of events. These have been identified as:
a) Extreme witness stress at the scene or during identification or during recall
b) Racial or cultural disparities
c) Alteration of the memory by the interviewer
d) Time

Recognizing the fallibility of witness memories, then, is especially important to participants in the judicial process, since many trials revolve around factual determinations of whom to believe. Rarely will a factual question result in a successful appeal.

Where available, most counsel prefer documentary evidence to eyewitness testimony. Historically, counsel have relied upon original photographs, letters written by the parties, and other “formal” documents. Recently, we have seen a significant increase in the use of digital information. There has been an explosion in the use of email programs and of cell phones to take videos and photographs. These “tools” will change the nature of trials. As demonstrated recently in the Jian Ghomeshi trial, the unearthing of 13-year old emails by the defence and their use to attempt to discredit a woman accusing Jian Ghomeshi of sexual assault underscores the growing importance of “digital debris” in criminal and civil trials. (*6)

The amount of electronic data, records and documents introduced in trials has risen dramatically in the last ten years, increasing the time and expense of trials. Individuals and companies alike are hanging on to emails and electronic information, such as photographs and videos, forever, given the practically unlimited storage space available on the web and on computers. It is common sense today for lawyers to ask if there is a likelihood that relevant electronic evidence is available, whether emails, text messages, social media posts, online reviews etc. Even when someone thinks they have deleted the electronic information, it may not be deleted. The information may still exist on the backups of company databases and service provider databases.

What can we expect next? More electronic information and, with it, the risks of alteration of the electronic information. It's the wild west, a brave new world. As before, with original photographs and documents, forensic investigators will be required to determine if, in fact, the electronic photograph or document has been altered. This also means the likely reduction of the use of eyewitness accounts and witnesses’ memories, without the aid of digital information. That might be a good thing. 
(*1) “Richard Alexander”, The Innocence Project,
(*2) Hal Arkowitz, Scott O. Lillienfeld, “Why Science Tells Us Not to Rely on Eyewitness Accounts”, Scientific American, January 1, 2010.
(*3) Ibid
(*4) See Elizabeth F. Loftus & J.C. Palmer, Reconstruction of Automobile Destruction: An Example of the Interaction Between Language and Memory, 13 J. of VERBAL LEARNING & VERBAL BEHAVIOR 585 (1974); Elizabeth F. Loftus, D.G. Miller, & H.J. Burns, Semantic Integration of Verbal Information into a Visual Memory, 4 J. of Experimental Psych, 19 (1978).
(*5) See Laura Engelhardt, “The Problem with Eyewitness Testimony a talk by Barbara Tversky, Professor of Psychology and George Fisher, Professor of Law”, Standford Journal of Legal Studies, April 5, 1999.
(*6) Laura Kane, “Ghomeshi email evidence shows how ‘digital debris’ increasingly used in trials”


Post a Comment

<< Home