Crime shows like Crime Scene Investigation (CSI) are a big influence on juries and create unrealistic expectations about forensic science.
This is among the issues New Zealand researchers are set to spend hundreds of thousands of dollars investigating.
University of Canterbury historian Dr Heather Wolffram received $350,000 of Marsden funding to investigate how juries deal with forensic evidence.
She said the CSI effect was a convenient description for the idea that "our popular culture is pretty saturated with images of forensic scientists as heroes and where forensic science is represented as providing certainty through physical evidence".
But the influence of popular culture was not new to CSI, said Wolffram.
"One hundred years ago you did get forensic scientists complaining of what we could call the 'Sherlock Holmes effect' giving a kind of skewed perspective to the public on how forensic science is conducted and what's possible to know through it."
Wolffram said juries misunderstanding expert testimony could lead them to devalue that testimony altogether "or make juries extraordinarily sceptical".
"What do we believe if we can't distinguish between the two experts? Will juries just make decisions based on whose rhetoric is more compelling?
"I guess another question is, are we not giving juries enough credit? Because you could say you know the difference between the way television portrays things and what real life is," Wolffram said.
Other experts spoken to by the The Press agreed TV versions could slant how juries comprehend forensic evidence.
Minister for Courts Chester Borrows, who came to the job with 24 years experience in the police, said crime programmes created an "expectation that there will always be forensic evidence, and the absence of it in some way detracts from a witness's credibility".
Independent forensic scientist Dr Anna Sandiford said she had heard of juries in the United States that had been told, "you are not going to hear DNA evidence, but that doesn't mean to say that ‘Mr Jones' didn't commit this crime".
"So people are actually having to be given a reason why they're not going to be hearing experts, because the expectation is that you must have it in order to be able to solve the crime," Sandiford said.
University of Canterbury dean of law Dr Chris Gallavin said CSI-type shows reinforced perceptions that "you can come to a categorical answer if you just look at it long enough".
"Scientific speak is very different to every day speak, and they never rule anything out. And then you think, how does that equate to beyond reasonable doubt?
"We bring all of our own baggage of who we are and what we've experienced, and whether we've got that from TV or from life, we bring that to the table," Gallavin said.
"And that's the real strength of a jury system, but it can also be a real weakness."
ESR forensic science manager Dr Jill Vintiner said the institute aimed to keep things understandable for the jury, and advocated to meet with lawyers before a trial to discuss evidence and results.
She said one thing was glaring from the CSI-type depictions of forensic work.
"It's certainly not as glamorous as it looks."
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