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Crime Technology

On the Dangers and Potential Abuses of DNA Familial Searching 163

Advocatus Diaboli sends a story of how a high tech forensic procedure almost led investigators to the wrong person. In 1996, a young woman named Angie Dodge was assaulted and murdered in Idaho Falls, Idaho. There was a conviction in the case, but later reports claimed the wrong man was in prison, and police thought there were more than one attacker anyway. This eventually led to the re-opening of the investigation. Using DNA evidence that had been preserved from the crime scene, police used a controversial technique called familial searching to try to find a lead. This method is used when there is no direct DNA match within the available databases. Instead, it tries to identify family members of the suspect. Police found a partial match, which eventually led them to Michael Usry, a New Orleans filmmaker. They convinced a judge to provide a search warrant to extract Usry's DNA and test it against the sample. It wasn't until a month after the extraction that they told him he'd been cleared.
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On the Dangers and Potential Abuses of DNA Familial Searching

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  • Non Story (Score:1, Insightful)

    by Anonymous Coward

    No mistake was made. The police checked a potential suspect and cleared him.

    • Re:Non Story (Score:5, Informative)

      by Anonymous Coward on Tuesday March 10, 2015 @07:31AM (#49223821)

      No mistake was made. The police checked a potential suspect and cleared him.

      Well, this should cause anyone using a DNA service or donating their DNA to science to think twice:

      The elder Usry, who lives outside Jackson, Mississippi, said his DNA entered the equation through a project, sponsored years ago by the Mormon church, in which members gave DNA samples to the Sorenson Molecular Genealogy Foundation, a nonprofit whose forensic assets have been acquired by Ancestry.com, the world’s largest for-profit genealogy company.

      What the actual fuck?

      • Came here to say the same thing. If I had mod points, I'd mod you up.

        I would also add, that now we know how powerful wide collection nets of metadata can be (eg, NSA surveillance), I wonder if other types of donation, such as bone marrow registries, are going to be subpoenaed and how that will affect donations.

        • Can you reasonably call a collection of DNA linked to names "meta" data? That's literally the most identifiable information possible.

      • Re: (Score:3, Insightful)

        by operagost ( 62405 )
        Also,

        â€oeI had lots of days sitting at the house with the dog,†he recalled in an interview, â€oewondering if these guys were going to use a battering ram to bust open the door and shoot my dog after he started barking at them.â€

        The public is increasingly fearful of the police. And it's THEIR FAULT.

      • I'm trying to figure out what part you are surprised at. That the mormons are interested in genealogy? No surprise there. That DNA is being used for genealogy purposes? No surprise there. That Ancestry.com, a genealogy company that has a history of buying up other genealogy companies, would want to get into the genealogy DNA business thru an acquisition? No surprise there. The only thing I can think of that would surprise you is that people were willing to pay somewhere around $100 to a non-profit to have t
    • Did the police then remove the innocent citizen's DNA record from all databases it was entered into against said innocent citizen's will?
      If not does:
      "The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."
      have any real value i

      • The inclusion of "papers" in the fourth amendment implies the protection of privacy, not just physical possession, and is parallel to DNA. Even before photocopies and data backups, "secure", when applied to "papers", obviously refers to the risk of disclosure of information without the owner's consent more than it does to the loss of that information. After all, truly important papers could have been manually copied and stored separately even in 1776.

        And did you miss the first item on the list: "persons". O

    • by sjames ( 1099 )

      I'll bet that 'suspect' would have preferred not to be molested by the police over what was akin to a fishing expedition. They had no actual evidence that he committed the crime. It seems doubtful that it was actually probable cause.

      They certainly owed him the courtesy of QUICKLY letting him know he had no need to worry about further suspicion hanging over him. Like doing their test IMMEDIATELY and letting him know within a couple days of taking the sample.

  • System worked, then? (Score:5, Informative)

    by CrimsonAvenger ( 580665 ) on Tuesday March 10, 2015 @07:19AM (#49223771)

    So, they got a warrant like they're supposed to.

    Then they executed the warrant, gathered a DNA sample, and tested it.

    Sample came back as not matching, so they removed the suspect from their list of suspects.

    So, what's the problem here? They checked out a lead (using legal methods, like a warrant), found it went nowhere, and continued the investigation into other possible leads....

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      If you are referring to the DNA clearing the guy -- then yes the 'system worked'. However, you are overlooking the fact that this familial DNA technique caused an innocent man to be inconvenienced and harassed.
      Why are people so complacent about the abuses of police and judicial system. A warrant should have never been issued for such a lousy technique.

      • If you are referring to the DNA clearing the guy -- then yes the 'system worked'. However, you are overlooking the fact that this familial DNA technique caused an innocent man to be inconvenienced and harassed.
        Why are people so complacent about the abuses of police and judicial system. A warrant should have never been issued for such a lousy technique.

        This isn't an abuse. This is the system working (as well as it can, though getting him in to the office on a lie is kind of skeevy). And since even the cleared suspect is considering the branches of his family tree even he's buying into the validity of the technique.

        • by Anonymous Coward

          And since even the cleared suspect is considering the branches of his family tree even he's buying into the validity of the technique.

          He's "buying into" it because they tell him it works. Except it doesn't. From earlier in the article:

          "Following this new lead, the police mapped out five generations of Usry’s family, narrowing their focus to three men.
          Only one, the New Orleans filmmaker, fit the mold of a plausible suspect, according to an application for a search warrant. "

          So it only led to one plausible suspect, and he was innocent. Meanwhile, this guy essentially lost a month of his life (I'm sure this guy didn't get much of anyth

          • Meanwhile, this guy essentially lost a month of his life (I'm sure this guy didn't get much of anything done in that time).

            Why should he have been worried for a month? He knew perfectly well he was innocent. Unless he'd been banging the victim, there was no way the DNA match was going to come back positive (other than him having an identical twin who was a serial killer). It's not like he was all "ohmygod they've finally found me out!!! I'm going to go to prison!!!!!"....

            • Re: (Score:1, Informative)

              by Anonymous Coward

              You do know that only a very small sliver of DNA is actually tested. There is a high change of collision when you are actually searching for familiar matching, you are basically searching for a birthday paradox here.

              There are calculations that have shows for every DNA there are 3000 people who will match it within the USA itself.

            • Re: (Score:2, Informative)

              by Anonymous Coward

              Why should he have been worried for a month?

              Have you not been paying attention the last few years? Government enforcers -- local and three-letter -- have established that they're willing to ignore the law and evidence in favour of roughing up and incarcerating somebody -- anybody -- regardless of whether or not they're actually guilty of anything.

            • by Immerman ( 2627577 ) on Tuesday March 10, 2015 @09:51AM (#49224877)

              My understanding is that DNA matches are generally not accurate enough to be accepted by scientists as a conclusive match, though perhaps the techniques have improved since then. That's actually a big part of the problem with them - people believe them to be considerably more accurate than they actually are. Maybe they're even 99% accurate, but that would still mean that there's a 1 in 100 chance that you'll come up as a false positive: enough to worry about I'd say. And if the accuracy isn't even that good... well it makes DNA databases being used for identification a bit worrying. Not so much because they're not useful, but because the police, lawyers, judge, and jury all tend to believe that a match is far more conclusive than it really is. Especially the jury, whose familiarity with DNA evidence comes from daytime television, where it *always* fingers the guilty party.

              Basically nobody involved is likely to have the grasp of statistics necessary to properly parse the results - even doctors, who you would expect to deal with false positives/negatives all the time often get it wrong. Test is 90% accurate, that means if you come up positive there's a 90% chance you've got the disease, right? Wrong. You also need to factor in the independent chance of actually having the disease. Say there's a 2% chance that a person chosen at random is infected: that means out of 100 people you will (on average) have 10 false positives and two actual positives: testing positive only means there's a 2/12 (17%) chance you're infected.

              Now consider DNA evidence - let's be generous and say it's 99.999% accurate: there's 400 million people in the US, so you can expect there will be 400,000 false positives, only one of which actually be guilty. Me, I don't like those odds.

              • Sorry, math error, that last line should be "4,000 false positives" - still more than enough to make me nervous

            • by Duhavid ( 677874 )

              "Why should he have been worried for a month? He knew perfectly well he was innocent."

              The legal/judicial system we have is not perfect. We read occasionally about people that are released from prison after being falsely found guilty ( with limits for error there as well... ).

              So, knowing you are innocent and not worrying are not mutually exclusive.

            • by sjames ( 1099 )

              He worried because innocence doesn't necessarily result in a good outcome in criminal proceedings. If it actually goes to trial, bankruptcy is often the reward for the innocent. Other times, they end up convicted anyway and lose years of their lives (or simply lose their life in the case of capital murder).

              So he was more like "OMG they think I brutally murdered someone, I'm going to prison and I didn't even do it!"

        • by Half-pint HAL ( 718102 ) on Tuesday March 10, 2015 @08:01AM (#49224029)

          This isn't an abuse. This is the system working (as well as it can, though getting him in to the office on a lie is kind of skeevy). And since even the cleared suspect is considering the branches of his family tree even he's buying into the validity of the technique.

          There was no concrete evidence, only circumstancial. I find it extremely worrying that he was brought in under false pretenses and that they granted a court order for the DNA sample before any request had been made to him for a voluntary submission.

          Even if someone is your only suspect, he shouldn't be treated as a "prime suspect" without evidence. Usry says in the article that he was worried that they were going to push for charges even when the sample came back negative, and it was the police and FBI's treatment of him that made him worried. It wouldn't have been the first time that an overzealous law enforcement officer had got so fixated on "getting a result" that they would have pushed on, ignoring the evidence.

          The biggest warning light in the article is actually an innocent-looking remark from the Sgt in the case: " “I wish it wasn’t a dead end, but it was.”" I know it's important to solve crimes, but no police officer should ever be disappointed to find out a suspect is innocent. Do you think that one-month wait was lab time? I doubt it. During all that time, some of the officers and agents involved may well have been pushing to continue, on the grounds that he probably passed through the town once, and they think it was a cousin of his, so they would be arguing that he "probably" drove his cousin up and was an accessory.

          There is always the danger with these speculative searches that you end up identifying a suspect then convincing yourself he's the guy, then confirmation bias leads the officers to build a case around lots of selective evidence. In a cold case, you'd be essentially building a "loser edit" for the poor sod you've picked.

          • by ranton ( 36917 )

            There was no concrete evidence, only circumstancial.

            It is a myth that circumstantial evidence is in some way useless. (probably caused by too many cop TV shows) It is not as good as direct evidence, but it is still good enough to obtain a conviction. For instance if you find the murder weapon and it has the suspect's DNA on it, you only have direct evidence than his DNA was in fact on the knife. It is circumstantial evidence of the suspect actually committing the murder, since you don't know for a fact how the DNA got on the knife. It could be enough to conv

            • For instance if you find the murder weapon and it has the suspect's DNA on it, you only have direct evidence than his DNA was in fact on the knife. It is circumstantial evidence of the suspect actually committing the murder, since you don't know for a fact how the DNA got on the knife.

              But that's a world apart from "someone probably (but not definitely) related to him did it, and he happens to know a few people who lived somewhere in the sort of vicinity, even though he didn't".

              • I can only imagine how ineffective the police would be if they couldn't even investigate someone until they already had irrefutable proof they were guilty.

                • There's a huge gap between "not investigating someone" and "going to the judge for a warrant before even talking to a guy who has a non-zero statistical possibility of being potentially involved." Seek the middle ground.
        • So the system is working is proved by finding some random fool to pin a crime on? And its ok to violate due process and basic logic and reasoning just because the cops had a 1 in 1 billion shot at finding the suspect...?

          I mean, this is a man that lives in New Orleans. Did they even check whether this person even came to Idaho? Has he ever been even close to Idaho?

          Why did they come after him in the first place? Because they have no clue who did it and they are scrapping the bottom of the barrel. We all

        • "Usry said he regarded his experience as an invasion of privacy"

          He is also an almost unknown New Orleans film maker who is now making a documentary about a well known murder case that he has a personal connection to and is getting national attention.

      • by Anonymous Coward

        But a witness could've just as easily caused the same thing. "It was John Doe my next door neighbor!" When people are talking about police abuse, this is not it.

        • So, just because a non-police citizen can lie about what they witnessed, then it's OK for the police to use lousy techniques with known flaws? WTF?

          You do realize providing false evidence in an investigation is a crime in itself in a lot of (most?) jurisdictions, right?

      • by schwit1 ( 797399 )
        ... "familial DNA technique caused an innocent man to be inconvenienced and harassed" So, investigative techniques that inconvenience and harass legitimate potential suspects should not be permitted? He was not picked at random. How are the police supposed to do their job? This would also kill all the cop shows on TV.
        • by Anonymous Coward

          This would also kill all the cop shows on TV.

          "It wasn't until a month after the extraction that they told him he'd been cleared." -- this realistic timeframe for analysis would also kill all cop shows on TV.

          • "Will the test results incriminate the accused? Will the police have to keep up with their tireless searching for evildoers? Tune in next week, same Bat-time, same Bat-channel, when we won't answer these questions! Then in two weeks, we probably won't answer them again! But if you tune in a month from now, we'll find the answers to these pressing questions!!"

        • He was identified on circumstancial evidence then treated as a prime suspect. Look:

          Detectives traveled to New Orleans in December and persuaded a magistrate judge to sign a search warrant ordering Usry to provide his DNA for comparison.

          The caller identified himself as a law enforcement official in New Orleans and said he was investigating a hit-and-run in City Park.

          They got a court order without ever asking the guy to help with their enquiries. They brought him in with an outright lie and forced him to give a DNA sample. That's treatment unwarranted by the evidence, whatever the judge thinks.

          • by Anonymous Coward

            They got a court order without ever asking the guy to help with their enquiries. They brought him in with an outright lie and forced him to give a DNA sample. That's treatment unwarranted by the evidence, whatever the judge thinks.

            You missed the important quotes of the article:

            âoeI didnâ(TM)t take it as a big deal,â Usry said. âoeHe said he wanted to get together, ask a couple of questions and take a couple pictures of my car.â Knowing he had nothing to hide, Usry agreed to meet

        • by jbengt ( 874751 )
          Investigative techniques used in this case are not proven and may cause enough false positives to be detrimental to serving justice against the actual perpetrators.
      • If you are referring to the DNA clearing the guy -- then yes the 'system worked'.

        No, I am referring to the whole "got a warrant, executed it, etc" process. Unlike, say, GCHQ or NSA, they didn't break the law in the process of investigating this guy. There was no miscarriage of justice to be found - he was a suspect, they determined (using legal means) that he wasn't the perp, done.

      • How often does that *not* happen during a police investigation - everyone who is interviewed or classed as a suspect that is later cleared undergoes the same "issue", its part of the process of the police investigation. If they had to avoid such an "issue", no police investigation would ever go anywhere.

    • by DarkOx ( 621550 ) on Tuesday March 10, 2015 @07:37AM (#49223879) Journal

      I think the problem here, if there is one (and I am with you on not being so sure there is) just how far removed from an event under investigation do you need to before you can't be subject to warrants related to it.

      Right now a Judge or Magistrate basically determines this. I am not sure what standards may exist beyond probably cause of finding evidence. So here we have a guy where there is nothing at all to tie him to the events except DNA match that is actually exculpatory in that its clear he isn't a match for the sample the Police believe is that of the perps; however it does indicate he may be a family member however distant. The police want to confirm this. Is it reasonable to "search" his blood to confirm the match, and is that than cause to search everyone one of his relations, and their offspring?

      Its kinda like the NSA's 3 degrees thing, does this simply open the door to the government being free to collect DNA samples form most citizens? We do need to look at some old assumptions in the face of new tech. In the past you had to manually do DNA compares between two samples, now you digitize results and search a database. Where you would not in the past have do a comparison with someone who could not have committed the crime now you effective compare with every sample taken from everywhere. Based on those past assumptions we figured limiting collection to convicts, voluntary submitters, and those we had probable cause for protected most folks privacy. An situation like this would be rare; if it did happen we probably would have permitted it; thinking the scope was highly limited, now it could easily pull most of us in.

       

      • by Idarubicin ( 579475 ) on Tuesday March 10, 2015 @07:57AM (#49223995) Journal

        So here we have a guy where there is nothing at all to tie him to the events except DNA match that is actually exculpatory in that its clear he isn't a match for the sample the Police believe is that of the perps; however it does indicate he may be a family member however distant. The police want to confirm this. Is it reasonable to "search" his blood to confirm the match, and is that than cause to search everyone one of his relations, and their offspring?

        Your summary may be a bit too brief for the nuances here. It appears that the police found a partial DNA match with the suspect's father (in, remarkably, a privately-maintained - not state-controlled - DNA database), which in turn suggested that a close relative would be match. The police then examined publicly-available genealogy information to identify candidate relatives. From the genealogy records the police narrowed their search to three candidate individuals. Using various other circumstantial information they finally sought a warrant to collect a DNA sample from just one individual.

        While I agree that there are legitimate "slippery-slope" concerns, based on the (admittedly brief) description in the linked article, it seems that in this particular instance reasonable steps were taken to minimize the scope and inconvenience (to potentially-innocent individuals) of the investigation. It wasn't a scattershot "We must test the DNA of all your male relatives!", but rather "We want to test the DNA of your one male relative whom we also suspect for reasons (a), (b), and (c)."

        • by Orgasmatron ( 8103 ) on Tuesday March 10, 2015 @09:09AM (#49224547)

          But they didn't suspect him at all. They found their suspect first, then constructed a circumstantial case (a, b and c) against him.

          This is dangerous shit and the police should get slapped for it. And the public needs to step up and make it clear to judges that we won't tolerate them rubber stamping bullshit warrants. Just because there was a happy ending this time doesn't mean that we aren't playing with fire. This guy came one lab mistake away from from having his life ruined.

          There was a time when most of us understood the dangers of working from desired conclusion to supporting facts. But now we celebrate people that work backwards, from cop shows on TV to "scientists" paid to push a political agenda.

          • But they didn't suspect him at all. They found their suspect first, then constructed a circumstantial case (a, b and c) against him.

            At the very beginning of any police investigation, police don't - or at least aren't supposed to - start out suspecting anybody at all. They are given (or they collect) information which leads to suspicions: testimony by victims or other witnesses, surveillance video, credit card and phone records, fingerprints, blood or semen at the crime scene.

            In this case, the police found one line of evidence - DNA from semen - that strongly suggested the crime was committed by one member of a family. They then used

            • It is a question of false positives. Fuzzy queries against huge databases give results. They are almost always false.

              Given a large database and the ability to do inexact queries, the conditional probability that you are looking at the guilty party, given a hit, is damn near zero. Statistically speaking, a hit is indistinguishable from a miss. And in this case, no one in the database committed the rape, no one related to anyone in the database committed the rape, and yet, the query returned a hit.

              If you

          • Bingo.

            The notion that one should bear the blame for a crime based on the notion that a family member may have been present is just disgusting. This is not Star Trek, and we are not Klingons.

            This should have been a career-ender for everyone involved... cops, judge, their supervisors; the whole bloody lot of them should be tossed out into the cold as unfit to serve the public under any circumstances.

            • The notion that one should bear the blame for a crime based on the notion that a family member may have been present is just disgusting. This is not Star Trek, and we are not Klingons.

              It's very fortunate that that isn't what happened, then, isn't it?

    • The system did not work, the warrant should have never been issued it was a fishing expedition wrapped up in "science". To start the used a commercial DNA database aka someplace that sucker innocents into submitting DNA samples (ancestry.com) for genealogical purposes with promises of anonymity and control. The first warrant broke that anonymity and led to the guys father even though they knew he was not a suspect. They then got a warrant to forcibly sample the son with the extra info of apparently he ha

      • sooner or later the police will be able to match everybodys DNA

        To the X number of people that are a 99.9% match.

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      Except now his police file says: "suspect in murder case, not proved"

    • by sjames ( 1099 )

      From TFA:

      “I had lots of days sitting at the house with the dog,” he recalled in an interview, “wondering if these guys were going to use a battering ram to bust open the door and shoot my dog after he started barking at them.”

      Sadly, we cannot claim his fear was unjustified. It certainly isn't without precedent.

  • They identified a suspect based on evidence and eliminated him using evidence.

    How is that abuse?

    • by Nidi62 ( 1525137 ) on Tuesday March 10, 2015 @08:36AM (#49224263)

      They identified a suspect based on evidence and eliminated him using evidence.

      How is that abuse?

      Because they used one piece of "evidence" (very tenuous at best) and just cast out a wide net to suspect someone from half the country away. It's the same as if a witness of a crime in New York said the suspect was 6'2" and blond so the police start interviewing 6'2" blond people living in Utah. Partial DNA matches should not be enough to get a warrant for someone who lives 1700 miles from where the crime occurred, especially if there is no other corroborating evidence.

      • It is more like searching an existing database, such as finger prints for close matches then proving the match with more up to date reference sample.

  • by Anonymous Coward

    Just because someones DNA was found at a crime scene doesn't mean they were there at the time of the crime or even that they were ever there. There have been enough cases forensics Labs accidentally contaminating evidence never mind the fact that even today DNA finger prints aren't that unique. Basically it should only ever be used as corroborating evidence.

  • So can someone explain to me why the FBI has carte blanche to run searches through the Ancestry.com database? It says they had a court order to reveal the name, but apparently no court order was necessary to do the check, why is that?
  • Which as much as an "art" as a tested science. In situtations of a partial fingerprint there are fewer characteristics to match a database. And they have been incorrect in the past as in the case of the Oregon lawyer mistaken for a Spanish terrorist. Although you may be given the broad odds of a mismatch, I wonder what if there have been actual studies. For example, randomly reduce fingerprint caharacteristics until there are multiple partial matches and see if any are correct.
  • DNA fingerprinting isn't completely unique. Now when used the normal way, testing someone who has come under suspicions for other reasons, a match may be unlikely enough that it has evidential value. But when the you reverse the process ("get me anyone in the country who matches this DNA whether we have any reason to suspect them or not"), there's a good chance of going after an innocent party as that group is going to have a number of people in it, all but one of whom is innocent.

    • Right on. I have used the Ancestry Y chromosome database and had a hit where ALL the alleles matched. I emailed the guy and we can't figure out how were are related: It's definitely way more than the number of generations Ancestry suggested was likely. So if one allele doesn't match you could be talking a common ancestor many generations back. That's not exactly a close relative.

      Ancestry's predictions for how close a match were not very accurate for the Y chromosome database. In fact, they aren't usin

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