The impact of social media on an eyewitness account of a crime is so powerful, investigators say it's reshaping the way they handle big cases.
The State of Oregon is known among lawyers and psychologists for practicing some of the best eyewitness identification procedures in the country.
The Multnomah County District Attorney’s office took things a step further by developing its own protocol which follows even stricter guidelines.
Even still, prosecutors say social media has a way of compromising their cases.
The use of social media during an investigation is somewhat of a double-edged sword. Without question, investigators say there are major benefits, explaining that more eyes on a shared photo of a wanted felon mean better odds that person is captured.
But sometimes online photo sharing can be detrimental to a case, especially when it comes to preserving the accuracy of an eyewitness account.
"Just like a fingerprint is ruined with spilled coffee on it, a memory can be ruined if it starts getting contaminated with other sources of information," Daniel Reisburg, Professor of Psychology at Reed College, explained.
Reisburg studies the human memory extensively. He says a witness to a crime is typically good at remembering faces, especially when that witness is emotionally involved in what happened.
He also said, though, that those memories are vulnerable and easily tainted.
"Often times, victims of a crime are curious to find out what happened, so they do their own amateur investigation,” Reisburg said. “They talk to people in the neighborhood, they get on Facebook to see what people are saying about crimes. That's done with the best of intentions, they're trying to figure out what happened."
While the intentions may be good, the outcomes may not, he explained.
"But, the difficulty with that is that pictures online could be bogus, something might be wrong, or maybe the information is true, but the problem is it becomes part of their memory,” Reisburg said. “If two people report it, and one person picked it up from another, it's misleading."
Investigators will sometimes throw out a positive suspect identification altogether when they realize a witness was influenced by something that person saw online.
"There was a robbery case where I had multiple victims and a booking photo was showed to one witness that hadn't been asked to go through the ID process. That was a problem," Multnomah County Chief Deputy District Attorney Chuck Sparks said. "The deputy had to find a different way to ID that person because the ID process itself was called into question, and we had to be certain we had the right person."
Sparks says it's nearly impossible these days to prevent a big case from being talked about online. But the DA's office is now taking steps to prevent mug shots in sensitive cases from being shared on the internet to preserve the memory of a prospective witness pool.
"In cases where an ID is ongoing, we'll try to withhold a booking photo for as long as it takes to complete ID process, and sometimes that can be months," Sparks said. "In some cases, witnesses will come forward much later in a case and if that happens we want to make sure that we get a clean ID and they weren't influenced by something they saw online."
Sparks says because of DNA evidence and cell phone records, it's rare these days that a whole case would hinge on a single eyewitness ID, but it is possible. Which means the work they do to preserve the integrity of their cases is critical.
"Eye witness accounts are part of big picture. It's one piece to the puzzle and of course, we're looking at all evidence," Sparks said.
Ideally, investigators say they like to talk to an eyewitness within the first 24-48 hours of when the crime occurred, mainly because it reduces the chance of their memory being tainted by things like social media.
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