Newsletters › Spotting and Remembering Invisible Gorillas
In an experiment called The Invisible Gorilla, subjects were asked to watch a video of two groups of people – one wearing white and the other wearing black. Subjects were told to count how many times the people wearing white passed a basketball. In the middle of the video, a person wearing a head-to-toe gorilla costume walks through the shot of the video. Amazingly, half of the subjects did not remember seeing the gorilla. In other words, divided attention can cause serious errors in perception and memory.
Many trials turn on eyewitness testimony. For example, former Dick Cheney chief of staff, Scooter Libby, was convicted of perjury and obstruction of justice based, in large part, on eyewitness testimony. Libby’s case turned on the credibility of competing recollections of a phone call that happened years before the trial, with no corroborating documents from either side.
Libby’s defense team attempted to admit expert testimony from Dr. Robert A. Bjork about the science of memory. Bjork’s proposed testimony included that (i) memories are not recorded, stored or retrieved in verbatim form, but rather memory is dynamic and prone to error, (ii) divided attention can cause serious errors in memory, and (iii) a person’s confidence in the accuracy of their recollections has little correlation with the accuracy of those recollections.
The court denied the defense motion to admit Dr. Bjork’s testimony, on grounds that the average juror understands, among other things, that “if A learns from B that B had been on vacation in Hawaii and then later learns from C that she spent her vacation in Jamaica, that A could later misremember where each spent their vacations because he was consumed with pressing matters.” United States v. Libby, 461 F. Supp. 2d 3, 13 (D.D.C. 2006).
That is undoubtedly true, as anyone who has ever been “consumed with pressing matters” can confirm. But the extent to which the mind distorts, embellishes and even creates memories depending on a variety of external factors is not yet common knowledge.
Studies have shown that people generally believe that memory works like videotape, a fixed recording of events that can be reviewed later to determine what happened. That view has been rejected by researchers who study memory. The false memories scholar Elizabeth Loftus has described memory as “like a Wikipedia page where you can go in and change it, but so can others.”
In a 2015 journal article that provides an overview of the science of memory, the United States District Judge Mark W. Bennett stated that academic studies and his experience on the bench have shown that “memories can be distorted, contaminated, and even, with modest cues, falsely imagined, even in good faith.”
Even the best memories are not immune to distortion. Judge Bennett describes one study in which people with “highly superior autobiographical memory” remembered seeing news footage of United Flight 93 crashing in a field in Pennsylvania on September 11, 2001. No such film exists. Hundreds of people vividly recalled that the comedian Sinbad once played a genie in a ‘90s movie called Shazaam, which does not exist. Their memories included detailed plot points and movie posters.
While everyone forgets things sometimes, very few people think that they can be tricked into remembering something that never happened. But documents powerfully affect memory, either by legitimately refreshing recollection or by creating new, inaccurate memories. In one study, Loftus gave participants a booklet that described three real childhood memories and a false one about being lost in a mall, and told the students that all four were real and took place with a family member. In follow-up interviews, 7 of 24 students remembered the false event in their booklet and even embellished it with their own details. As Loftus put it, “the study provides evidence that people can be coaxed into ‘remembering’ events that never happened.”
These studies have obvious implications in the courtroom. First, every lawyer must be prepared to refresh witnesses’ recollections with documents, videos, and prior statements. Second, in cases that depend almost entirely on eyewitness testimony, lawyers should be prepared to provide judges with jury instructions summarizing the reasons why eyewitnesses make mistakes. In 2012, New Jersey’s Supreme Court issued jury instructions explaining the way memory works and certain factors affecting the reliability of eyewitness identifications. While these instructions were designed for criminal cases, they can and should be adapted for relevant civil cases.