Pennsylvania court rulings differ on expert witnesses

Allowed to testify on memory fallibility, not false confessions

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The state Supreme Court last month put Pennsylvania in line with 44 other states by allowing experts in the fallibility of human memory to take the stand in criminal cases where the identification of a suspect by witnesses is an issue.

But on the same day, in what scholars are calling a wholly inconsistent opinion, the same court -- though with a different majority -- found that experts who study the phenomena of false confessions may not testify.

The two disparate opinions raise questions about the court and what impact those decisions might have on the state's criminal justice system.

"It's as if these opinions come from two different worlds," said David Harris, a law professor working at the University of Pittsburgh.

"They're incompatible," said Jules Epstein, a law professor at Widener University. "Either the science is good or it's not. Either jurors should know this stuff or they should not. I don't see any inherently logical distinction."

Scientific studies have shown significant flaws in human memory, particularly with regard to witness identification during a traumatic event.

Particular problems arise in cross-racial identifications and where a weapon is involved.

According to one study noted in the recent state Supreme Court opinion, out of the first 200 post-conviction DNA exonerations, nearly 80 percent of those defendants were found guilty based on witness identification.

In the case of Commonwealth v. Walker, Benjamin Walker was charged with two armed robberies in Philadelphia in October 2005. The only evidence connecting him to either robbery was witness identification by the victims.

Walker's attorney asked to call at trial an expert on the fallibility of human memory, but, citing a state Supreme Court opinion from 1995, the trial court denied the motion. The judge found that an expert would have an unwarranted appearance of authority, and the same effect could be accomplished through cross-examination and closing arguments.

Walker was found guilty in one of the robberies and ordered to serve 171/2 to 35 years in prison.

He appealed but the state Superior Court upheld the trial judge, writing that it found itself "constrained to apply the consistent precedent of our Supreme Court until it rules otherwise with regard to this type of evidence."

The Pennsylvania Supreme Court agreed to take up the issue and heard arguments on March 7, 2012. Walker argued that the flaws of human memory have been studied extensively, and that there is now general acceptance of those findings in the scientific community.

Walker's attorney also argued that cross-examination is not an effective tool on the issue.

"This is especially true, according to [Walker], when witnesses, although mistaken, sincerely believe what they say is true."

But the prosecution argued that allowing expert testimony would be unfairly prejudicial because it "invites the jury to abdicate its responsibility."

"Rather than making jurors more sensitive to identifications of varying quality, the commonwealth postulates that expert testimony makes jurors skeptical of eyewitness identification, undermining the credibility of both relatively strong and relatively weak eyewitness testimony," the Supreme Court summarized.

Further, the prosecution argued that allowing experts to testify on witness reliability would open the courts up to "hundreds or thousands" of potential claims for ineffective assistance of counsel.

But in the court's opinion, remanding Walker's case back for trial, Justice Debra Todd wrote that that concern should not outweigh the value of the evidence.

"Since our [previous] decision ... 20 years of advances in scientific study have strongly suggested that eyewitnesses are apt to erroneously identify a person as the perpetrator of a crime when certain factors are present," Justice Todd wrote. "[A] vast body of scientific research about human memory has emerged. That body of work casts doubt on some commonly held views relating to memory. From social science research to the review of actual police lineups, from laboratory experiments to DNA exonerations, the record proves that the possibility of mistaken identification is real."

But in a scathing dissent to the Walker opinion, State Supreme Court Chief Justice Ronald D. Castille accused the majority of acting like "lemmings" by following other courts' direction across the country. Before Walker, Pennsylvania was one of only four states -- the others are Louisiana, Kansas and Nebraska -- that had a formal exclusion of witness experts.

"The no-record 'scientific' conclusion here will be to ensure that some of the most brazen of criminals -- perpetrators of stranger-upon-stranger violent crime -- will walk away scot-free, all because of the generic opinion of some on-call social-scientific 'expert' on a matter that can be explored by ordinary trial means (effective cross-examination and specific jury instruction) and decided by ordinary jurors, as the record in this very case makes abundantly clear," Justice Castille wrote. "I am also skeptical, in the absence of any record demonstration and testing of the 'science' proffered here, because the science happens to dovetail so nicely with the preferences of the criminal defense position."

But Mr. Harris questioned Justice Castille's dissent -- and his apparent disdain for social science.

"He does not understand what it is to do science. He seems to think science only has to do with test tubes and Bunsen burners -- that there can't be science on human nature,' Mr. Harris said. "There's no real dispute about what the scientific evidence shows.

"That's been true for a long time, and that's why most states allow experts in eyewitness testimony."

False confessions

Although people have difficulty believing someone would confess to something he didn't do, Mr. Harris said, it "absolutely" does happen.

According to Richard Leo, a law and psychology professor at the University of San Francisco who has studied this issue extensively, there are two types of false confession.

A "compliant" false confession given by a suspect to end an interrogation more quickly and possibly be treated more leniently; and a "persuaded or internalized" false confession given because a suspect believes he may have committed the crime, even though he may have no memory of doing so.

In the Pennsylvania Supreme Court case on the issue decided last month, Jose Alicia was charged with criminal homicide after an innocent bystander was shot and killed in a Philadelphia cafe in November 2005 following a dispute between two groups.

Mr. Alicia confessed to the crime, but prior to trial, his defense attorney asked to be able to call Mr. Leo to testify about false confessions. The defense noted that Mr. Alicia has an IQ of 64, is considered to be mentally retarded and has been on Social Security disability for most of his life. His confession -- and the self-serving statement of a man also at the shooting -- were the only evidence against him.

But the prosecution argued that it should be up to the jury to decide if a defendant's confession is false and that any expert's testimony on the matter would be mere speculation.

The trial court granted permission for Mr. Leo to testify generally about interrogation techniques, but he would be forbidden from talking about specifics of the case.

The commonwealth filed an interim appeal, and the state Supreme Court heard arguments on the matter in September 2012.

In the majority opinion, siding with the prosecution, Justice Seamus McCaffery, wrote that the justices were not persuaded by other courts that have allowed experts in false confessions and instead found that it "constitutes an impermissible invasion of the jury's role as the exclusive arbiter of credibility."

Instead, he continued, general testimony about certain interrogation techniques would invite the jury to determine those were used in the particular case, and therefore any confession would be unreliable.

The majority went on to say that even if a defense expert were used, the prosecution would likely counter with its own.

"We cannot conclude that expert testimony as to such generalities would help the jury to understand the evidence presented or to determine a fact in issue," Justice McCaffery wrote. "Ultimately, we believe that the matter of whether [Alicia's] confession is false is best left to the jury's common sense and life experience, after proper development of relevant issues related to ... the particular circumstances surrounding the elicitation of his confession, using the traditional and time-honored techniques of cross-examination and argument."

The court's decision means Mr. Alicia's case will go to trial with no expert testimony on false confessions.

Mr. Harris called the decision "weak" because it didn't address the scientific studies on the matter whatsoever.

"It's there. It's well done. It's reliable," he said. "And yet, it's not even mentioned in the Alicia opinion. They just ignore it. That explains why they can come to such different conclusions [from Walker]." But he continued, "it doesn't make it less contradictory.

"One opinion takes account of the science and one does not. That is troubling."

Sometimes, Mr. Harris said, a court will ignore facts and evidence to reach the decision it wants. When that happens, he continued, "you end up with law that is inconsistent and doesn't serve any overall purpose."

What will likely happen, instead, he continued, is that either the Legislature or independent law enforcement agencies will address the issue of false confessions by implementing their own mandatory audio and video recordings of suspect statements, as is encouraged by the American Bar Association.

That is already underway in Allegheny County.

District Attorney Stephen A. Zappala Jr. in early 2013 asked both the Pittsburgh and Allegheny County police to begin recording their interviews with homicide suspects, and the practice is being expanded to all county departments dealing with serious felonies.

"I don't think you need an expert to explain what the jury can see for themselves," Mr. Zappala said.

Further, he continued, the recordings will "completely eliminate cross-examination about coercion."

As for the question of calling experts on witness identification, Mr. Zappala supports it.

"Every time we have the opportunity to use the sciences, it hopefully presents a more just result," he said. "If somebody is convicted for a crime they didn't commit because we didn't use the science, that's the worst thing that can happen."

Paula Reed Ward: or 412-263-2620.

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