As science has long demonstrated, eyewitness accounts are frequently riddled with errors. Human memory in general is far from perfect—working less like a video camera than an ever-evolving collage, studies have shown.
But in courtrooms across the country eyewitness testimony of alleged crimes have frequently been enough to convince juries to send defendants to jail—even without more reliable forms of evidence.
Now, the courts seem to be finally catching up with the science. The New Jersey Supreme Court on Wednesday overhauled the way its state's eyewitness testimonies would be treated. The ruling is aimed to "educate jurors about factors that can lead to misidentifications," Chief Justice Stuart Rabner said, The New York Times reported.
A recent survey found that some 63 percent of U.S. adults thought that memory passively records events, per the video camera model. And the same survey found that more than one-third of respondents thought that one witness's "confident" testimony is enough evidence to convict a suspect. In nearly three-quarters of cases in which DNA evidence has exonerated a suspect, eyewitness testimony was involved in the original conviction process.
Not only can people often miss obvious details in a scene (such as a person in a giant gorilla costume), but they can also be led, with relative ease, to "recall" things that never actually occurred. These so-called false memories can be implanted intentionally or accidentally through poor questioning methods. "Misinformation has the potential for invading our memories when we talk to other people, when we are suggestively interrogated or when we read or view media coverage about some event that we may have experienced ourselves," Elizabeth Loftus wrote in 1997 in Scientific American. Loftus is a psychologist at the University of Washington who has studied the field for decades.
Because New Jersey has previously led other states in judicial reform, its ruling is seen by many in the legal community as a good omen for the rest of the country, which follows eyewitness guidelines from a 1977 U.S. Supreme Cour. Eyewitness misidentification is one of the most frequent reasons for wrongful convictions.
"The fact this court embraces the science may very well have a ripple effect all over the country," George Thomas, a professor at Rutgers University Law School told The Wall Street Journal.
The state's new standards require juries to hear about factors that might have influenced a witness's ability to effectively identify a suspect, including how long the witness had seen the crime, how long after the crime the witness was asked to identify a suspect, the distance between the witness and suspect, and if the suspect was of a different race than the witness. The ruling will not keep eyewitnesses out of New Jersey courtrooms altogether, but those who support the ruling—which passed the state's Supreme Court unanimously—say that it should help to curtail that type of testimony's power over juries' imaginations.
Also see this 2010 Scientific American MIND arrticle, "Why Science Tells Us Not to Rely on Eyewitness Accounts."