- Associated Press - Wednesday, May 28, 2014

HARRISBURG, Pa. (AP) - Pennsylvania criminal defendants won the right to offer expert testimony about the reliability of eyewitness identification in a decision Wednesday by a divided state Supreme Court that overturned a 20-year prohibition against it.

The four-justice majority ruled that Pennsylvania will join the great majority of states and federal courts when it comes to letting an expert tell jurors about research into eyewitness testimony.

“Twenty years of advances in scientific study have strongly suggested that eyewitnesses are apt to erroneously identify a person as a perpetrator of a crime when certain factors are present,” wrote Justice Debra Todd for the majority. She said it was “beyond serious contention that the statistical evidence on eyewitness accuracy is substantial.”

The court ruling outlined the conditions under which the evidence can be allowed and put the decision in the hands of trial judges.

“While we need not precisely define such situations, generally speaking, it would be where the commonwealth’s case is solely or primarily dependent upon eyewitness testimony,” Todd wrote.

The case involved Benjamin Walker, convicted of a 2005 robbery of two University of Pennsylvania students in Philadelphia, based on the victims’ identification of him to police. Walker is serving up to 35 years in prison.

The two dissenting justices argued that a better approach would be to amend the instructions about eyewitness testimony that judges give juries before deliberation. In most cases, the experts will be for the defense, wrote Justice J. Michael Eakin in a dissent joined by Chief Justice Ronald Castille.

“And if experts may opine about identification, why would they not be equally admissible on other peripheral matters, such as witness recollections of time, dates, places, colors, types of cars, clothes, directions and a host of matters which any given witness is likely to confuse?” Eakin wrote. “There being no logical difference, likening this decision to the camel’s nose under the tent is not an exaggeration.”

Castille defended the ability of jurors to use common knowledge and experience to assess credibility of witness identification.

“Before modern movements in psychiatry and psychology, mankind already had a rich literature laden with insight into humanity,” Castille wrote, adding later that “matters affecting human perception and recall are hardly the exclusive and special bailiwick of social science experts.”

Prosecutors argued that expert testimony on the topic of eyewitness identification is much more likely to cause unfair prejudice to the prosecution than it is to fairly help the jury, according to the majority opinion.

But Owen Larrabee with the Defender Association of Philadelphia, which represents Walker, said in an interview that the decision could make it less likely that innocent people will be convicted in Pennsylvania courts.

“I certainly hope so,” Larrabee said. “That was certainly our intent in pursuing the admission of this testimony.”

Larrabee said the next step will be to try to persuade the trial judge that the evidence they want to put on is relevant and has scientific validity.

Hugh Burns with the Philadelphia district attorney’s office declined comment, saying he had not yet read the justices’ opinions.