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Do juries expect magical fingerprint machine?

|Written By Jennifer McPhee

On television shows about crime scene investigators, the gorgeous and buff characters are confronted with bizarre scenarios, yet somehow manage to find slam-dunk physical evidence to convict surprisingly attractive culprits just in time for the credits to roll.

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Some say the “CSI effect” raises jurors’ expectations about what kind of forensic evidence they can expect police to deliver from every crime scene in the real world.

“If I only come to court with a single fingerprint or a single piece of DNA, they are either going to think I’m stupid or lazy,” says Richard Devine, team leader at the Ontario Police College’s forensic training unit.

Devine was speaking on the topic of expert evidence in criminal proceedings: strategies for avoiding wrongful convictions and acquittals, at the Osgoode Professional Development Conference.

Police are also expected to have the same kind of sophisticated and magical equipment and techniques as they do on the tube, he says.

“Unfortunately, the jurors are sitting down and they’re saying, what about your magical fingerprint machine? What about the machine that tells you if you find a fingerprint at your crime scene, and it belonged to her, and if you assigned the colour yellow to her, you should find yellow fingerprints all over the place.”

And even when the science on television is realistic, the scenarios aren’t, Devine later tells Law Times. “The bad guys in this province just drive by and shoot you. There’s nothing special about that. A good forensic investigator should be able to place the shooter. But I don’t want any bias that says a good forensic officer would have done this because that’s what they do on television.”

Devine says one impact of these shows is they’ve made real world forensic investigators more professional and careful. Jurors are coming in looking for what they’ve seen on television, and also want to know how the Crown got the evidence and what it means for the trial, he says.

“Where people used to go to sleep during the forensic stuff, they don’t anymore. They are wide awake and they are listening. And they have a standard and that standard is created by the media,” says Devine.

But others say the CSI effect is more myth than reality. Toronto defence lawyer Alan Gold calls it “a bit of common prosecutorial folklore that they use to rationalize their losses.”

Gold says these shows give defence counsel the ability to point out all of the forensic evidence that’s missing from a case. He says prosecutors equally argue that not every case has forensic evidence, and sometimes call police witnesses so they can ask them at trial whether it’s surprising that certain kinds of evidence were not found.

But whether these shows actually influence jurors is a separate question, and a recent study published in the Loyola of Los Angeles Entertainment Law Review says they don’t, says Gold.

This study, “The CSI Effect and Other Forensic Fictions,” looks at whether these shows seduce jurors with promises of forensic evidence, resulting in an epidemic of unjustified acquittals.

The study’s author, Kimberlianne Podlas, writes that CSI effect claims are not grounded in case studies or statistical data of acquittals, but on anecdotes about cases where law enforcement lost but believed it should have won.

She summarizes the effects-based literature about the entertainment media’s contribution to the public’s understanding of the law. And then, applying this research, she subjects claims of a CSI effect to a set of empirical investigations.

In the first part of her investigation, she surveys assistant district attorneys, and finds most of them believe the CSI effect exists and has thwarted their own prosecutions. But the majority of these cases actually resulted in convictions, which disproves any CSI effect, she writes.

Next, Podlas examines whether the CSI effect influenced 538 mock jurors. The study pool was made up of 98 people on jury duty, 134 jury eligible adults, and 306 university students.

“Contrary to the hype, the empirical data does not support the existence of a CSI effect - at least not one that perverts guilty verdicts into wrongful acquittals,” Podlas concludes.

“Indeed, the data shows that CSI-viewing mock jurors did not rely on CSI factors in reaching their verdicts (to any greater or lesser degree than did their non-viewing counterparts),” she writes. “In fact, only a very small portion of either group referenced such factors at all. Accordingly, it does not appear that there is a CSI effect in light of the empirical data.”

Juries and likely even judges probably put too much weight on expert evidence, but this problem existed long before these television shows, says Toronto defence lawyer Mara Greene, one of four lawyers representing the Criminal Lawyers’ Association at the public inquiry into the actions of discredited former Toronto pediatric pathologist Charles Smith.

When an expert speaks, the tendency is to accept that evidence blindly, which is why there is an admissibility test and why juries are warned not to put too much weight on expert evidence, says Greene.

Expert evidence can and has led to wrongful convictions, she says. One reason for this is that what’s considered solid science at the time may be discredited a few years later. For instance, stomach contents were once viewed as an appropriate way of determining time of death, she says. “People were convicted based on that science and that science, with more knowledge, has been discredited,” says Greene.

Another problem leading to wrongful convictions is that two experts sometimes interpret the same evidence and give different, but reasonable, opinions based on it, she says.

“That interpretation can go two ways, maybe more sometimes, and how does a jury or trier of fact determine which one is right when the experts can’t even figure it out?” she says. “I don’t know if they can, and that’s part of the problem. I don’t think, in the present system, they are given enough [skills] to make those decisions, which is why we’ve got to be very careful with expert evidence.”

Most jurors take their duty very seriously, says Greene. But even a juror weaned on CSI will tune out when the expert is boring or the evidence is over their heads, she says. CSI-type shows use gripping language and fancy cinematography, and that’s what keeps the viewers interested, not the content per se, she says.

“I think part of being an expert witness is learning how to convey the information in a way that people hear it,” she says. “That’s also part of the problem, because the expert who is the better story teller or more likable and charismatic might not be the right expert. But I think we’re people and we don’t assess things.”

When it comes to CSI-type shows, Greene says she thinks, or at least hopes, that people have a healthy cynicism about what they see on television.

“When we see a sci-fi show, we don’t all of a sudden believe in UFOs,” she says. “No one watching Star Trek concluded that Klingons exist.”

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