Forensic DNA Mixups | Greg Hampikian | TEDxBoise


Translator: Desiree Kramer
Reviewer: Denise RQ Thank you. Today I’m going to talk
about some serious stuff, and then hopefully, we’ll have
a little bit of humor along with it. I brought some props. I’m going to need some help from some
people in the front row to commit a crime. (Laughter) And for the serious part,
I’m going to be talking about DNA errors, forensic DNA errors today. So imagine – and I’m only going to ask you
to imagine this briefly – a loved one is hurt or killed in a crime. Someone’s finally arrested,
you go through the endless trials, and someone is incarcerated
for the crime. You think you’re done with it. Twelve years, 20 years later,
you hear they got the wrong person. That’s the kind of thing
that we are trying to avoid. And so, in order to do that, we have to constantly
be looking at our techniques to see how to improve them. So I’m going to talk about some issues
in my own field that I’ve seen in my work. I work in all 50 states now, I have cases overseas:
Asia, Africa, Europe. And some of the things I’ve seen
that I’m concerned about, that I have raised
at professional meetings, some of it has never been shown before,
and I’ll show you tonight. So we’re talking
about forensic DNA errors. I don’t want to you to think it’s all bad, it’s not all bad,
it’s a great field, it’s my life. And I’m going to break it
into two categories: one is statistical
and interpretative errors, so things where the conclusions are wrong,
based on human reasoning and mathematics, and the other one is contamination,
which is kind of easy to understand. Somebody spills some DNA
while it gets transferred, and then I’ll tell you what my lab
here in Boise is working on in the contamination area very briefly. So we’ll have a first slide, I’m going
to turn you into the DNA experts. Get ready for science, here it goes. This is the easy stuff,
this is a single source, I can teach you guys
to do this immediately. Let’s say I decide I’m going
to commit a crime with this. It’s clean, it just got out
of the dishwasher, and there was bleach in the dishwasher,
so it has no DNA on it. I touch it, and I go to the front row,
and I commit a murder. The police come, they do the spatter, they collect some of the blood
to identify the victim, they see my fingerprint, and they — I always carry a swab. (Laughter) I really do always carry — They take a swab, they swab it,
and what’s really nifty about these swabs is you can just knock
the ends off of them, but I’m going to pull it,
and put it in here. I should be wearing gloves etc., etc. (Laughter) OK. Now, the issue is am I the murderer? Here I am, the suspect, and all you have to know about DNA is you get it from your mother
and your father. So that means that every location
on the DNA that I’m going to look at – and I’ve shown you these are
four locations here, in the columns; sorry that this is a little off – at every location you’ve got one number
from mom, one number from dad. I’ve got one number from my mom,
one from dad, I’m the suspect. Am I a match? (Audience) Yes. Greg Hampikian: My students,
when I say the word ‘match’, have to say ‘statistics’. So, am I a match? (Audience) Statistics. GH: At this level, maybe one in 10,000 people
would be included in this match, maybe one in 2,000, something like that. Alright, that’s a single source,
everybody gets it right. Next. Here is a mixture. How do we get a mixture? Before I commit the crime,
a couple of other people I offered– touch this, maybe three of you. So now, they come in, and they do
the swab, and they get a mixture. This is what they get: these again
are four locations of DNA, but now, there is a bunch
of what we call alleles or sizes in there. The question becomes,
“Am I included in that?” So, am I still included,
or are all of my sizes in there? (Audience) Yes. GH: Is it a match?
(Audience) Yes. GH: The statistics is now something like
one in 10 or maybe one in 50. And that’s because more people
could potentially be included. Now, you think
that this would be an easy concept, we’d have mathematics
that can deal with it, but when laboratories
are given the same data, they’d sometimes vary
in that statistic over ten to the 10. That’s the difference
between going to court and say, “There was 30 dollars
of damage to my car,” and “The damage to my car was greater than the combined
gross domestic product of every country over the last 100 years” and then sum. (Laughter) So the statistics are done
differently in different labs, and they give a very different impression
based on how the statistics worked before. This mixture question
becomes very complicated, and if you give a mixture to ten experts, you might get
ten different interpretations. I did that. I took a mixture case from Kerry Robinson, a man who wrote to me,
and who says he’s innocent, and he was convicted
in a gang rape in Georgia. There were three men who raped a woman. One man was identified, all of his DNA in the semen
was recovered from the victim. She picked him out of a yearbook. He’s given an option
to reduce his sentence: tell us who one of the other guys is. He makes up a name, the guy doesn’t exist. They say, “No deal.” Then he says, “Kerry,”
and he can’t remember the last name. “Robinson,” he finally says. And so they arrest Kerry Robinson,
the guy he knew in high school. Kerry says, “He only gave my name because he thinks
I talked to the cops about him.” But, because he gave a name,
his sentence is reduced. That man, the first man is
out of prison right now. Kerry Robinson is in prison. I looked at the DNA, I say, “Kerry Robinson is excluded
from that mixture.” I took the same data,
me and Itiel Dror my co-author, and we gave it to 17 analysts
at the same lab, another lab – sorry, we all work in one lab, but not the first lab that did the DNA – and we asked them,
“Is it a match? Is he excluded?” – you didn’t say statistics – GH: Is it a match?
(Audience) Statistics. GH: Alright, you got a pass. Is it a match? Is he excluded? Thank you. Or is it inconclusive? We gave it to 17 experts, all trained, in one lab in North America,
all part of a state lab. We got all three answers. Not only we got all three answers
but only one of the people at that lab agreed with the lab
in Georgia’s original conclusion that Kerry was included. Next, we got a little attention for that,
and new scientists picked it up, and economists picked it up,
but it’s still a problem. All right, I was trying to explain
this mixture question to a prosecutor over the summer,
so I had to use some scrabble tiles. And what I said is a mixture is like if you put my name and your name,
Mr. Prosecutor, in a bowl. We put two people in,
but you can pull lots out. And so I had to do — I took our two names and these are
the letters for our two names. Now, we’ll get into this question
of subjectivity and bias. Who contributed names to this? I’ve told you, I did it. You might not know how to spell my name. But Al Gore did too, didn’t he? George Will, Larry King, Mary Kay,
Porky Pig, Anne Klein, Henry Miller, Happy Gilmore, Lina Horne, Papa Gino,
Pepe Le Pew, Marilyn Monroe, Willy Wonka, Rainman, King Phillip,
King Lear, King Kong, etc. The point is these mixtures, even though we go to court,
and they say that is the person a match (Audience) Statistics. the statistics can widely,
widely, widely vary to the point
where they can become meaningless, and there is no uniformity
in my field for that. Next slide. This is just some of the attention
we got for that article. And I’ll take the next one. Here is another problem of statistics. This is a very unfortunate case. Mr. Denman became a missing person. This is from the Albuquerque newspaper,
this is his obituary, he was 49 years old when he left us,
and donations can be sent, etc. There is another article about this later,
when they interviewed his brother, because they found the bones
near the house, and they thought it was a murder. FBI came in to identify,
“This is Donnie Denman,” with DNA they identified it, so there is another article looking for
people who could help solve the murder. Next slide. This is now four months later. Donnie is not dead. His friend was putting newspapers down
to his parents’ car in the garage, saw that there is
an obituary for Donnie Denman, and that there was a funeral,
called Donnie Denman and said, “They think you’re dead,”
and he said, “Who gave the oration?” He said, “Your pastor.” He called the pastor,
he straightened it up. This shows you that even though
there was a DNA match, right, a FBI DNA match — People. (Laughter) Even though there was a match– (Audience) Statistics. the statistic wasn’t that high,
this is mitochondrial DNA, a particular type of DNA,
we use on old bones, broken hair etc. And it doesn’t give us
those powerful statistics. Next slide please. This is our last story of statistics,
this was my first case in Taiwan. And this is for
the Taiwan Innocence Project. They heard from a man “Mr Chen”. So I’m going to show you how to read this. This is now Y-chromosome DNA, so most of the columns
will just have one number. I’m sorry you can’t see it that clearly, but this is DNA recovered from semen
from the underwear of a rape victim. She was raped by three men,
and these are the alleles or DNA sizes that were found. This is Mr. Chen. Now is Mr. Chen’s 15 there? Yes. In fact, every one
of Mr. Chen’s alleles is there. Mr. Chen is arrested,
Mr. Chen is convicted, he loses all three appeals,
he writes the Taiwan Innocence Project. They needed me when they came over
to stage, show me the state, and they say, “What can we do,
what’s the statistic on this?” And we try to calculate the statistic,
it was pretty strong. I said, “But there are new tests.” So they went to court in Taiwan,
and they got a test that instead of looking at
the number of alleles in the first kit, added some other alleles,
some other markers in this kit to look at. So they looked at more locations,
more powerful statistics. Even though he was included with the less powerful statistics, with the more powerful,
– here is Mr. Chen – his 17 is not in the underwear, his 13 is not in the underwear. Next slide. This is Mr. Chen in March of 2014. So, it’s a statistical problem. It was a match. (Audience) Statistics. And now we have a better kit
that looks at more sides, and so gives us more powerful statistics. We’re going to talk about contamination. Next slide. This is a Los Angeles case. You hear about the test tubes
all the time, that people who work in labs,
like I do, work with. But you might not know
that these are the sizes we work with now. They all look the same. There is writing on them. You can’t see it, right,
even if you work on it — So the position of the tubes
is what’s important. And now I’m going
to teach you the principle that I try to teach my people in lab, “Do not keep your arsenic
in an old spice bottle.” (Laughter) And if you do, don’t put
the arsenic in the spice rack. And so, when you’re handling
a suspect’s DNA, and DNA from a crime scene, you have to do the crime scene DNA first. Get it all the way to paper,
till you’re completely done with it before you take out the tube
of the suspect’s DNA. Why? (Audience) Contamination. GH: Contamination
or you just might mix up a tube. Does that ever happen? By the way, a lot of experts testify,
they can’t possible make a mistake. They’re keeping track of everything. I just heard this story in Montana,
a couple of weeks ago, by an analyst. And here is the– Can we go back one slide? Maybe not. What I was showing you
is from a Las Vegas case. They’re apologizing. Why, what happened? They had two suspects’ DNA in line, somebody accidentally swapped
the tubes in the lab, it happens. They told the wrong man,
“Your DNA is a match.” You’re going to prison
for 30 years if we try you. Maybe if you plea guilty,
you’ll do seven, ten, I don’t know. He plead guilty. What would you do? You’re going against DNA. And then, they realized
there was a mistake, because another lab
got the same DNA result and told them, “You made a mistake,” and so they let the man go,
they apologized. OK, next. (Laughter) This is a horrible crime, 1968,
a 13 year old girl is murdered, raped and murdered in New Jersey, and in 2004 a cold case unit
works on the case. They have underwear from the poor girl, they get some DNA from it, male DNA, they get a profile
that matches to a convicted offender. He’s got to be guilty, right,
a convicted offender. I read about it in the New York Times,
and I’m like, “Hooray, DNA has done it. Then they say, “Oh shoot, we had
this guy, Jerry Bellamy’s DNA in the lab at the same time as the underwear,
the same day. Maybe it was contamination. I thought, “Oh my gosh,
this guy is going to get off.” The poor sisters of Jane Durrua
have been pushing for this for years, to get this conviction,
to find out who killed their sister. Next slide. Turns out, it was contamination. Because they took other clothing
from the murder, that had never been to the lab, sent it to a lab
where none of these guys’ DNA had been, got a match to another convicted offender,
who everyone believed did it, but that convicted offender died
before he could go to trial. So that’s another contamination issue, this time in a laboratory
between evidence. Next. This is one of my cases in Georgia. Carlton Gary is one of the longest
serving death row persons in Georgia. He wrote to us saying he was innocent. He wrote to a lawyer saying
he was innocent, he contacted me. I got to work on the case, and working
with the Georgia Bureau of Investigation. We looked through all the old evidence. He was convicted of being
the Columbus stalking strangler, a man who killed a bunch of older women,
raped and killed a bunch of older women, in the 70s, in Columbus, Georgia. And we got some of the clothing
from the women, we found biological stains
on the clothing, we tested it, the GBI, the Georgia Bureau
of Investigation tested it, and they got a DNA profile,
“not Carlton Gary.” We were very excited. Put it in the FBI database,
national database, nothing happened. We waited two years, somebody commits
a crime in Georgia with a gun that matches the DNA
that doesn’t match Carlton Gary. I said it several times. (Laughter) I don’t remember. (Laughter) So I don’t remember the statistic,
but it’s convincing. And it is definitely a match. So there is two crimes in Georgia,
the rape murders from 1977, the gun from a crime
just two years ago, they match. (Audience) Statistics. GH: Just leave it. (Laughter) They go after the guy, they find him, the guy with the gun can’t possibly
be the guy who committed these rapes. He has not the right age etc.,
they start researching, and what they find out is
that it was a contamination in the lab. On both of these pieces of evidence, with the same DNA
that was in the laboratory. There is no way
I can find an explanation for this because that sample of DNA
that contaminated them is a semen sample, produced by someone who works
in the lab as a quality controller. Imagine your job,
if your job is producing — (Laughter) I am not saying you should do this
at work by the way. Don’t come to me if you do. (Laughter) In any case, so this remarkably, rare,
supposedly almost impossible thing, in a carefully controlled laboratory, have contamination happened twice,
in this case that I’m working on. It does happen, it is a worry. Next. This is the Phantom of Heilbronn. My mom lived in Europe
for most of her life, and I’d go visit her
and I’ve heard about the Phantom. She is a woman who is
involved in six murders, and another mysterious death. She is found in syringes
that heroin users discard on beaches. She is found all over Europe
committing crimes. They don’t know who she is, they sample all these women,
hundreds of women in Heilbronn, no match. They can’t decide who it is. Thank you. (Laughter) Good it was all the same DNA,
a 100% match to the DNA of this woman. Thank you. Can we stop the game? Can we stop now? (Laughter) You get an A, but now stop. (Laughter) What happens,
is they go through all of this — You know this is
a huge Interpol case, 15 years. And what is it? A lady who works in the swab factory
took some work home. She got contaminated on the swab,
she’s never committed a crime in her life. Why wasn’t that detected in 15 years? People use swabs in labs for controls. If there was a central agency
looking at unexpected results, looking at our contamination results,
they can put this together quickly. The truth is labs don’t talk
about their errors. You have to subpoena that information, you have to force them
to disclose that information. It is not the way science should be. Science should be looking for its errors
and publicly disclosing them. It’s good science, but there are problems. The best way to find problems
is be open about them. Next. So, what is my lab doing about it? Well, this is an idea
we came up with years ago: that we would use DNA sequences
that don’t exist in nature, so I’ve discovered them,
we call them nullomers: the smallest sequences of DNA
that don’t exist in nature. A cool, little idea,
kind of a party trick, and now we have made markers out of them,
and we strung them together. So this is the marker. So, if you have to give a sample,
to the police say, – see this band here,
that is my nullomer marker. This is a DNA profile, those numbers
that we have been looking at come off of these charts,
but our marker shows up glowing. So if you give the sample,
and the marker is in it, it’s right there. And if even we dilute your DNA,
we put it in water, so that it is only one part per million
of that original sample, and dilute it there,
that marker is still there, even though your DNA
has been diluted out and not detectable. So those of our nullomer markers,
it’s our contribution. Last slide. This is Michael Hash,
I worked on his case for many years. His DNA did not free him,
there is nothing we could find, but great lawyering did. Thank you very much for your attention. (Applause)

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