DNA Sampling of Innocent-Until-Proven-Guilty People Is on the Rise

By Eliza Strickland | April 20, 2009 6:16 pm

DNA testIf you’re arrested for a felony in the state of California, expect to give up a DNA sample. As of January 1, California police departments began taking and storing genetic samples from all adults arrested for felonies, regardless of whether they go on to charge those people with crimes, or whether the suspects are ultimately convicted. Meanwhile, the FBI and 15 states now collect DNA samples from immigrants who are detained, and 16 states store genetic samples from people found guilty of misdemeanors.

The intent is to create a large genetic database that will allow police to solve more crimes, but critics say the cumulative effect may be unconstitutional. Criminal justice experts cite Fourth Amendment privacy concerns and worry that the nation is becoming a genetic surveillance society…. “What we object to — and what the Constitution prohibits — is the indiscriminate taking of DNA for things like writing an insufficient funds check, shoplifting, drug convictions,” said Michael Risher, a lawyer for the American Civil Liberties Union [The New York Times]. 

U.S. courts have generally agreed that law enforcement agencies have the right to take and store DNA samples from convicts and former convicts on parole, but they haven’t yet weighed in on whether suspects (who are innocent until proven guilty) must give up DNA samples as well. In Europe, however, the courts are already wrestling with such cases. British police have been taking genetic samples upon arrest for years, but in December the European Court on Human Rights issued a legally binding decision stating that keeping DNA samples from people who have never been convicted of a crime is a violation of their right to a private life.

Law enforcement agencies argue that taking genetic samples is akin to routine fingerprinting. Rock Harmon, an adviser to crime laboratories, also says that even if an innocent person’s DNA winds up in a genetic database, it would come to nothing without a crime scene sample to match it. “If you haven’t done anything wrong, you have nothing to fear,” he said [The New York Times].

Related Content:
80beats: European Court Says Police Can’t Keep DNA Samples from Innocent People
80beats: Fancy Fingerprinting Could Tell if You’ve Been Misbehaving
Discoblog: DNA Cops Crack Down on Flower Theft and Other High Crimes
Discoblog: Criminals, Beware: Your Name Might Be in Your DNA
DISCOVER: Q & A with Eric Juengst—discusses the FBI’s genetic database

Image: iStockphoto

CATEGORIZED UNDER: Health & Medicine
  • http://clubneko.net Nick

    You think that’s bad? You have a criminal record tied to that DNA too! “Arrested on suspicion of felony.” That NEVER comes off. Once you have been suspected of something, regardless of how innocent you’re proven, you still have a criminal record and DNA samples tied to it. Since you have a criminal record, you’re automatically more suspect if you’re mistakenly caught again.

    True story, a friend of mine was arrested on a warrant, because a 5’4″ asian guy knew his name and address and gave it when caught for a crime. My friend was 6’5″ and white. The asian guy happened to be his adopted brother, and confessed, so my friend didn’t get in any trouble, other than a night in lockup, fingerprinted, and a permanent criminal record.

  • T Sh

    “If you haven’t done anything wrong, you have nothing to fear,”

    This sentance is completly wrong.

    See article below.

    There is a real danger in finger-print and DNA data-bases that not everone is aware of.

    A Mistaken DNA Identification?
    What Does It Mean?

    Updated OCTOBER 2000

    [This entry has been rewritten, corrected, expanded and modified
    by taking into account comments received from readers.]

    By Andre A. Moenssens

    Various press reports released in early February make mention of a British case wherein a local police department confessed to having identified an innocent person as a criminal by a DNA test that was said to be in error. A U.K. police agency that had secured near 100 convictions on the basis of DNA testing, admitted that, as far back as April of 1999, they had matched a sample taken from the scene of a burglary to six loci on the DNA molecule of one of 700,000 persons whose DNA was collected in the national database. The suspect was a man with advanced Parkinson’s disease, who could not drive and could barely dress himself. He lived 200 miles from the site of the burglary. His blood sample had been taken when he was arrested, and then released, after hitting his daughter in a family dispute. He was arrested despite his protestations of innocence and alibi evidence that he was babysitting a sick daughter at home. Police dismissed these protestations stating that “it had to be him” since the DNA matched. The odds of the arrestee’s DNA being wrongly matched against that of the crime scene were said to be one in 37 million.

    It is only when the suspect’s solicitor demanded a retest using additional markers, after the suspect had been in jail for months, that further testing was done. This testing, using a total of 10 loci, showed an exclusion at the additional four loci. The interpretation of the original test’s results, given by law enforcement officials, were proven to be inaccurate. The suspect was then released from custody. The new British ten-loci test, it is said, only “offers a one in one billion chance of a mismatch” according to Scotland’s Evening News of February 9, 2000!

    Was the result reported after an examination of six loci an “erroneous” or “false” identification? No. There was indeed a “match” at six loci. What confuses lawyers, judges, lay persons, and indeed the police who make use of the results, is that they do not understand the true meaning of the statistics used by the experts. All but the initiated believe that when a DNA “match” is reported with odds of one in 37 million, we will encounter a like match in the DNA pattern only once in 37 million people. To test whether this is a common misunderstanding, the author [Prof. Moenssens], when lecturing to some 100+ trial judges, asked them what they understood the meaning of the testimony to be. All those who responded viewed the report as having said that this defendant’s particular DNA pattern would occur only once in 37 million individuals.

    According to DNA scientist Keith Inman, co-author with Norah Rudin of the recently published treatises An Introduction to Forensic DNA Analysis (CRC Press, 1997) and Principles and Practice of Criminalistics (CRC Press, 2000), it should be understood that the calculated frequency is an estimate, and can be off by an order of magnitude in either direction. Further, Inman said that “studies show that when databases grow, more loci (more discriminating loci) are required to support a strong inference of a common source.” In other words, despite the statistical calculation of 1 in 37 million on six loci, that does NOT mean that the six loci cannot match more than one person in 37 million. According to population geneticists, it is indeed possible to have the six loci match in perhaps many dozens of individuals whose DNA is contained in a databank of 700,000.

    Knowing that the non-expert judges, lawyers, and lay jurors will take the one in 37 million testimony to mean what it appears to say, is it ethical for a forensic expert to testify to the staggering statistical probabilities without explaining what the true meaning of the testimony is? And what obligation does the DNA analyst have to tell the jury that they must integrate the DNA evidence with other evidence when deciding whether the suspect is the perpetrator?

    Keith Inman regards a “hit” (or “match”) as nothing more than probable cause to look at the individual whose DNA has been matched to a sample stored in the database more closely, not the definitive and final disposition of his future in the criminal justice system. He states that “detectives and attorneys (perhaps even a few forensic scientists) need to be much better educated about the inferential nature of physical evidence. With well informed investigative people, the potential for arresting innocent people, as perhaps occurred in the U.K. case, will be minimized, while with ill-informed or biased agents, mistakes will happen with 13 loci, too.” [Emphasis supplied by editor.]

    The police in Great Britain maintain a DNA database which has grown from 470,000 potential suspects in 1998 to over 700,000 during 1999. The U.K. database is managed by the Forensic Science Service. It is now reported that ten loci will henceforth be used routinely when comparing known samples against unknown DNA fragments. The FBI is reported to test 13 different loci, which minimizes the chance of matching an innocent suspect by chance. State and local laboratories, however, do not always test as many loci as are used by our top national law enforcement agency.

    Will this result in wholesale appeals by the thousands of persons convicted through DNA testing? Stephen Niezgoda of the FBI is reported to have characterized the possibilities as “mind-blowing” in a story that appeared in USA Today on February 8. The story also suggests that U.S. officials recognize similar mismatches may occur here as DNA testing occurs more routinely. The American database of DNA specimen is reported to be about half of the one existing in the U.K. The larger the database, the greater the possibility for adventitious hits, which is how Mr. Inman characterized the British case.

    Perhaps a disturbing sidelight is that this misinterpretation of the statistical results in light of the case circumstances was revealed by British authorities only in January of 2000 when a law enforcement conference of DNA specialists worldwide met in Washington D.C. The mistake was not publicly acknowledged for almost a year after it occurred. When British authorities were questioned about the failure to reveal the error, a Home Affairs spokesperson said, “No system is 100 percent foolproof.” It must also be noted that the retest was done at the insistence of the defendant’s attorney. The unlikelihood of this suspect being able to commit the crime of which he was accused did not spark the retest. Forensic Science Service officials were said to have refused comment on the case to the press.

    The U.K.’s Daily News of February 11, 2000, reported that when the mistake was discovered some six months later, the arrestee was released without an apology and given a brief letter stating that charges against him were being dropped because “there was not enough evidence to provide a realistic chance of conviction.” No admission of error to the innocent person who had been arrested was to be forthcoming. The cavalier way in which law enforcement agencies deny making mistakes, and admit them only when the evidence is so overwhelming that errors can no longer be denied, does more to undermine the public confidence in law enforcement than the mere fact of the discovery of an error itself would do.

    Yet, DNA reliability has been lauded nationally as the most reliable evidence known, and persons criticizing the meaning of the proffered statistical calculations have been treated as lunatics and “Neanderthals.” It is clear that many people do not understand statistics, and law enforcement officers, prosecutors, defense attorneys, judges and jurors should also understand that DNA matches based on six DNA loci – or whatever number of loci tested – are not the end of the inquiry, but only the beginning of more investigative hard work.



    Additional Articles in Evidence Law…….
    New 02/05/04 The Origin of Legal Photography
    Amendments to the Federal Rules of Evidence
    Plaintiff’s Expert “Flunks” Daubert Test But Is Permitted To Testify…..What Can The Reviewing Court Do?
    A Mistaken DNA Identification….What Does It Mean? Revised 10/20/00
    Innocents Exonerated By DNA – But What If There Is No DNA? Have Innocents Been Put To Death?
    Instructing Jury That DNA Testing Is “Reliable Scientific Technique” Held Improper By Appeals Court
    DNA Statistics Found Insufficient to Convict without Corroboration
    All Expert Evidence Must Be Proved Reliable, Court Says
    Keeping Junk Science From The Courtroom . . .

    Return to Master Index

  • chris

    I think they should take a DNA sample at birth.

    Currently DNA tests take some time so they wouldn’t be able to readily identify somebody based off of a DNA test, however it is a useful source of non-witness information.

  • Tommy


    You actually trust the police? every single one of them? and how about every other person that couldget their hands on that information?
    How would you like it if yuor insurance company tripled how much you have to pay because you have some genetic disorder.
    How would you react if you got fired from your job because you have a gene that is common in criminals despite you being the paragon of virtue?

    For gods sake man! protect your privacy!

    OK the job example is a bit of a stretch, that woun’t happen for at least two decades the way we are going.

    I have no idea how to convince you that you are being stupid so i’ll just hope you get beat up by a cop one of these days so you know not to trust authority this much.

    Ooh thought of another argument: There is a reason you are allowed to carry guns, and its to make sure your govt is afraid of you. They exist to serve you not the other way around.

  • Jo

    @chris: did you even skim T Sh’s article? Read the title, even?

    From a practical standpoint, a database required to hold everyone, guilty and non guilty alike, rather than just convicted offenders, would be so horrendously bloated and so likely to procure false matches that either it will be far too expensive to test enough loci to maintain quality comparisons or many innocent people will end up being accused of crimes they had no part in.

    And to assume that members of law enforcement are always responsible with their power … is naive. I say that because the cops I’ve met, while not necessarily being bad people, are still just human, like you and me. They are not infallible. More power is more power to be abused, whether it be malevolently or earnestly.

  • Larry Donn Gillihan

    Hooray for Tommy’s comment: “There is a reason why you are allowed to carry guns, and it’s to make sure your govt is afraid of you. They exist to serve you not the other way around.” Right on the money, Tommy! And if we don’t stop them, they’ll disarm us and throw us in jail for giving a cop a dirty look. It’s time we forced our employees in the government to obey the constitution. We have to complain constantly to the government, then file charges against any employee who violates the constitution, and lawsuits to force them to obey it. I am sick and tired of hearing about innocent people in jail, many of them on “death row”.
    It has gone far enough. It’s strange that, when someone in prison is proven to be innocent, many of the police, judges and prosecutors who put him there obeject to, and try to delay, the release as long as possible. That should tell anybody what’s going on; they don’t care whether he’s innocent or not, they just want a conviction…it’s good for the political reputation, you know. If we’ll start throwing these errant employees in jail for convicting innocent people, the nonsense will stop.

  • Roy

    Why tolerate corruption at all? I say any public official or Law Enforcement Officer found to have committed a serious abuse of posistion or power should face the Execution Chamber.

    Every abuse is an abuse to the Constitution, every lie by public officials endangers it.

  • Terry

    Anyone who thinks that “innocent mistakes” have no effect, think again.

    My son was arrested for felony theft. Not only was he innocent, no crime was actually committed–the stolen money was misplaced by the store owner who filed the criminal complaint and then subsequently found by another employee.

    The charges were dropped “with prejudice” and the criminal record “sealed”. The result? Loss of a job offer at a financial institution because of a background check before the record was sealed–despite providing court documentation of the dismissal and statement of no crime committed.

    A background check on another job after the record was sealed resulted in a report that “No record exists”. However, in a separate email to the potential employer, the agency reported that although the record does not exist, “there is something I can’t tell you about”.

    That’s the result of “innocent mistakes”. Don’t ask me to give a DNA sample, and I will never, ever talk to police without a lawyer present.

  • Sapient Hetero

    Rock Harmon obviously lives on a different planet than the earth I know and love. Our justice system is rife with incompetence and corruption, and if your DNA, fingerprints, facial image, iris image or whatever is in some database that is searched in connection with a criminal case there is a non-zero chance of your being inaccurately associated with the crime. If they aren’t in the database, you’re safe from official errors.

    I don’t mean to say that EVERYONE in the justice system is incompetent or corrupt, just that there are enough who are to be concerned. Read John Grisham’s non-fiction book, “The Innocent Man” and you’ll be worried too.

  • geeta

    The law-enforcers are do their jobs just like most other professionals do – so as to put themselves in a better light, not necessarily to do the job right. They are more focussed on solving/closing the cases rather than getting the truth out, just like the finance companies are more interested in giving more high-interest loans, thinking someone somehow will pay all that interest and the principal, than protecting/honoring their depositors money. Scientific research is great, but they are just that and good for making stuff to make us more comfortable, where failing of some claims is acceptable. However, using these unreliable tools in the justice department can only lead to more insustice done in the name of one crime rather than getting the truth out. Equipping people under pressure (from the job or by influention people) with manipulable, statistical tools like this would further defeat the purpose of law-enforcement.

  • Brian

    Re: “If you haven’t done anything wrong, you have nothing to fear,”. Words to live by. NOT!!

    Has anyone ever noticed a certain proclivity amongst the law enforcement community? They like to talk about “suspects”. It’s a shadow of suspicion cast upon anyone branded as such.

    I don’t blame the police. They have a hard job and they deal with some really awful people. I’m thankful they deal with them so I don’t have to. However we need a realistic view of law enforcement; they are subject to the same human foibles and bureaucratic issues everyone else is.

    Only criminals convicted of major crimes should be in DNA databases used by police.

    Oh, and this WILL result in some criminals getting caught later (or perhaps even not at all). You cannot deny that DNA samples from everyone would be a useful law enforcement tool. The problem is that the price is too high (not in terms of money, but in terms of freedom). This is a price society simply needs to pay in order to protect the truly innocent.

  • Debbie

    My 12 yr old was accussed of csc 1&2. The DNA excluded him as the donor. It matched closer to the girls own DNA (father or brother maybe)? The prosecuter told the jury that her DNA mask his DNA and so he had to have done it, they found him guilty. Now my son faces a lifetime of crap coming down on his head for something he didn’t do. We want to appeal but the lawyer says if we do they could lock my son up until his 19 because he’s not confessing to the crime Why the hell would he, he didn’t do it. The system is screwed up so bad it’s not even funny. There is no justice in this world. All they care about is getting that all mighty dollar. MAY THEY ALL BURN IN HELL HOLDING HANDS FOREVER!!!!!!!! I always told my son tell the truth and everything will be all right, i guess the courts system made me out to be a liar, didn’t they???

  • Debbie

    my son has now passed a lie detctor test with flying colors, not an easy thing to do for anyone, but he did and the courts won’t stop their bull—-!! we have MORE than enough evidence to prove his innocents, but the courts just keep pushing!!!

  • Debbie

    now have a new lawyer, my son has passed a 2nd polygraph and we have found out that there was NO SALVIA in her underwear—the courts still won’t stop!! Maybe this will help–WE HAVE A HEARING WITH THE SUPREME COURT. Maybe they’ll start to back off now!!! We can only pray they will because MY SON IS INNOCENT!!!!!!!!!


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