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Crime.
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You know that thing that was almost solved
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-by a flasher dog in 1980's.
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But specifically this story is about
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how we increasingly solve crimes using forensic evidence.
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It's that thing that is just a staple of TV crime shows.
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Pull it from the torso on the left.
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Pull it from the boat on the right.
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Two hearts beat as one.
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Matches up perfectly.
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That's a match.
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We've got a match.
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And it just found us a match.
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Visible match.
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-We've a match. -Match.
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Were you able to determine
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which monkey bit him?
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The bite marks match those of the monkey found at the scene.
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Wow!
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That last one was presumably
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from one of the crossover episodes where the team from Law & Order,
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worked a case with the cast of Monkey Law and Monkey Order.
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-But...
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on TV and in real life forensic science plays
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an important role in criminal convictions.
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Prosecutors often complain about a so called C.S.I. effect,
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where jurors expect to see forensic evidence in every case.
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The problem is, not all forensic science
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is as reliable as we've become accustomed to believe.
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A report in 2009,by the National Academy of Sciences
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found that many forensic scientists
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do not meet the fundamental requirements of science.
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And a report last year by a Presidential Science Council agreed saying that,
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"expert witnesses have often overstated
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the value of their evidence, going far beyond
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what the relevant science can justify,"
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and that's the thing here.
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It's not that all forensic science is bad,
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'cause it's not, but too often,
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it's reliability is dangerously overstated
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and one sign of that is that forensic experts in court
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are often nudged to use one very convincing phrase.
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To a reasonable degree of the scientific certainty...
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To a reasonable degree of scientific certainty...
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To a reasonable degree of the scientific certainty...
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Within reasonable scientific certainty...
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To a reasonable degree of scientific certainty...
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Are you able to say that within a reasonable degree
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-of the scientific certainty? -Yes.
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And here's the thing that phrase
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does have a persuasive ring to it. Unfortunately,
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as that Presidential Council pointed out,
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it has no generally accepted meaning in science.
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It's one of those terms like, basic or trill
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that has no commonly understood definition.
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Am I trill?
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Is that good or bad?
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I mean I do feel trill, so I'm guessing it's awful.
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And-- when bad science
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is confidently presented, terrible convictions can happen.
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In fact, among the hundreds of people
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who have been exonerated by DNA testing since 1989,
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in nearly half of their cases,
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there was some misapplication of forensic science
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and there are people behind those numbers.
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Take Santae Tribble, who was convicted of murder
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and served 26 years. In large part,
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thanks to an FBI analyst who testified that his hair
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matched hairs found at the scene.
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And as he will tell you,
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the evidence was presented, as being rock solid.
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They said they matched my hair
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in all microscopical characteristics.
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And that's the way they presented it to the jury
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and the jury took it for granted that, that was my hair.
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But you know, I can see, why they did.
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Because who other than an FBI expert
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would possibly know that much about hair?
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Except of course,
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whoever stalled Amanda Seyfried at the 2009 Oscars.
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Breath taking waves,
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without loosing any of their body or bounce.
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-Stunning.
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-Stunning!
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-Stunning.
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-Stunning.
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Stunning! Stunning! Stunning! Stunning! Stunning! Stunning!
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The jurors in Tribble's case, were actually told
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there was one chance in ten million
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that it could be someone else's hair, and guess what?
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He was exonerated.
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Because once DNA analysis became available, his lawyer tested
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the thirteen hairs from the case
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and not only were none of them his,
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some of what they found was incredible.
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Nine of the hairs had come from the same source,
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a couple had come from different sources
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and one was a dog.
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Two different FBI agents who had, eh,
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looked at that and analyzed it, didn't recognize that it was dog hair?
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It was a K9.
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It was a domestic dog, yes.
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My personal conclusion was,
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-the dog committed the crime.
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Okay.
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So, first, it is amazing that he is able to laugh at that,
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but second, if a dog did commit the crime
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there's really no recourse there because there is actually no law
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against dogs committing murder
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and that's a fact that learned in Air Bud 9,
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Fuck the Paw-lice!
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And it turns out,
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Tribble is not the only case where FBI experts
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overstated their confidence in their results.
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The Innocence Project
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and the National Association of Criminal Defense lawyers
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found from the 1970's through 1999,
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in 268 cases where FBI hair analysis led to a conviction,
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257 or 96 percent of them had errors in analysis.
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Oh, it gets worse
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because nine of those defendants had already been executed,
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which is horrifying.
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And you would expect FBI hair analysis
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to have a high rate of accuracy than your friend's hair analysis
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of you can totally pull off bangs,
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because you can't,
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you absolutely can't, believe me I couldn't,
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just learn--
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-learn from our mistakes kids.
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Save yourselves!
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It's too late for me.
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And look,
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it's by no means,
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just microscopic hair comparison which has had
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the reliability of these results overstated.
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Those reports that I showed earlier suggests
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there is weak scientific support
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for some aspects of techniques like
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a blood pattern, footwear, firearm and bite mark analysis.
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And you must be familiar with that last one from
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cool scenes like this:
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A little 3D magic for clarity and I give you
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the killer's incisors.
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(COMPUTER BEEPING)
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Oh, Yo!
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The computer rated it "Yellow rectangle."
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And we all know yellow rectangle is the highest level of match
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a computer can give you about teeth.
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(AUDIENCE LAUGHING)
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Look, in the real world, bite mark analysis
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is highly subjective and unreliable.
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The President's Council found the entire discipline,
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does not meet the scientific standards
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for foundational validity.
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Which I believe, is science speak for "Bullshit!"
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But people have been sent to prison
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on the basis of bite mark testimony by experts like,
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Dr. Michael West.
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The science of bite marks analysis, is very accurate.
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NARRATOR 1: When it comes to bite marks,
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West consider himself "The maestro."
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He's found bite marks on a decomposed body
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submerged in a swamp,
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on a corpse that had been buried for more than a year.
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He's even used a bite mark
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taken out of a bologna sandwich to get a conviction.
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Now, that sounds impressive matching a killer's teeth
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to a bite mark in a bologna sandwich,
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although, you should know that the defendant in that case,
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got a new trial after an autopsy report
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found that the murder victim
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had actually eaten a small amount of bologna
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consistent with the amounts bitten off the sandwich.
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-(AUDIENCE LAUGHING) -So, that sandwich,
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was irrelevant to the case.
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In fact, you could even argue that it was actually Dr. West,
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who was full of, say it with me,
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-shit. -(AUDIENCE LAUGHING)
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And-- that is not the only issue
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that has arisen from his testimony.
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There are now five cases
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where he testified for the prosecution
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and where the charges were dropped
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or the conviction was later over turned
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and even West himself
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has admitted that he no longer believes
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in bite mark analysis for identifying perpetrators
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and he doesn't think it should be used in court.
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And yet, incredibly,
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every time a defendant has challenged its validity
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the court has ruled it admissible.
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And a key reason for that
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is that judges often rely on precedent
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to decide what to allow in front of a jury. So,
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if a particular discipline has been in court before
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it is likely that a judge will admit it again.
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All of which means that as the co-founder
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of the Innocence Project points out,
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decisions about the validity of science are being made
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by people who don't necessarily know much about it.
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Historically, we had a situation where,
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two scientifically illiterate lawyers
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argued the bonafides of scientific evidence
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before a scientifically illiterate judge,
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so the 12 scientifically illiterate jurors
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could decide the weight of that evidence.
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And if you think about it, that's absolutely terrifying.
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Trials can often be a situation when no one
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really knows what they are doing.
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It's like a cooking competition for toddlers,
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hosted by a stray cat and judged by goats.
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-(AUDIENCE LAUGHING) -Oh.
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The tuna was under cooked
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and covered in cold spaghetti sauce.
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You then for some reason
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cover the whole dish in honey nut cheerios.
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-I loved it. -(AUDIENCE LAUGHING)
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And look, none of this is to say,
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that there is not reliable forensic science out there.
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Finger prints and DNA
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are obvious examples but while we think of them as perfect,
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it is important to know
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they are by no means infallible.
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The FBI has found fingerprint analysis
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could have a false positive rate
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as high as one error in 306 cases.
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And a dramatic example of this
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came after the Madrid's train bombings in 2004
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when the FBI arrested this Oregon man, Brandon Mayfield.
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He had never even been to Spain in his life.
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But, three separate examiners, matched his finger prints
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to one on a bag of detonators. So, he was at that point,
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completely fucked!
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Until, investigators happen to determine that,
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that fingerprint actually also matched someone else
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who was in Spain at the time and that blew the minds
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of finger print experts.
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MARK ACREE: We always assume
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that finger prints are very very unique,
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but what the Mayfield case demonstrates, is that
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parts of a fingerprint can be
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so similar, it's possible for two people to be
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identified to one print.
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That's true.
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It turns out that two people can have finger prints
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that are so close that even experts can't tell them apart.
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Meaning that we are now this close
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to finally proving my theory. There is only one Olsen twin.
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She's just moving very fast
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-back and forth. -(AUDIENCE APPLAUDING)
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She confuses your eye.
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Now, I don't know how this new information helps me, yet,
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but when it does, the end is-- No! You frauds! You frauds!
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(AUDIENCE APPLAUDING)
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And then-- there is DNA,
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which is the gold standard in forensic science for a reason
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because in perfect conditions
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it's seen as the most reliable form of evidence, but
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not all DNA tests are equal
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and crime scenes can produce DNA of widely varying quality.
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NARRATOR 2: