But courts retain broad discretion to decide
An Illinois appeals court has overturned a man's conviction because the trial court did not allow expert testimony on the fallibility of eyewitness evidence.
The case involved Walter Allen, who was sentenced to 43 years in prison for a 2001 robbery-shooting. The robbery was committed by two men wearing hoodies who entered a dry cleaning business, demanded money, and shot a woman employee in the back. From her hospital bed, the woman identified Allen from a photograph as the shooter.
At Allen's trial, the judge refused to allow an expert witness to testify for the defense about problems with eyewitness identification. The judge said that the testimony of Dr. Steven Penrod, a respected psychology-law professor at the John Jay College of Criminal Justice, was unnecessary and might confuse the jury.
In its opinion in People v. Allen, the appellate court pointed to research establishing that eyewitnesses are often wrong, and that jurors have misconceptions about eyewitness accuracy. It cited prior Illinois rulings stating that expert testimony can dispel myths and correct misconceptions, and that "the science of eyewitness perception has achieved the level of exactness, methodology and reliability of any psychological research."
The court said it is not intending to lower the bar and allow all expert testimony about eyewitness accuracy. Judges are still entitled to exclude such testimony in some cases, but first they must carefully scrutinize the proffered testimony and determine whether it is relevant and might be helpful in the specific case. At Allen's trial, the court said, no such careful scrutiny took place.
Traditionally, trial judges are given wide latitude to decide whether to allow expert psychological testimony. For example, in a high-profile murder case in Michigan, a judge last week refused to allow either the defense or the prosecution to call dueling experts.
In that case, Thomas Richardson is accused of pushing his wife Juanita off a cliff at the scenic Pictured Rocks Cliffs. The defense claims that the death was accidental.
In denying both a defense motion to call a clinical neuropsychologist and a prosecution motion to call a forensic psychologist, the court said that the experts' testimony reflected competing opinions rather than science.
"The vagaries of the human mind and spirit are part of the puzzle left to a jury," wrote Alger County Circuit Court Judge Charles Stark. "Nothing proffered can assist them in determine the manner of death."
More commentary on the Allen decision is online at the Eyewitness Identification Reform blog.