That's the case in France where DNA samples are taken on any person arrested, whether they committed a crime or not, including demonstrators (or bystanders) in a political march.
The national DNA database now includes over 5 percent of the population and it is a great tool for the police since the authors of serious crimes typically have almost always committed petty crimes before. It also means that you can solve small crimes like burglaries with DNA.
It is a bit worrying from a privacy protection point of view though. And I barely see this database ever questioned by the French press.
> That's the case in France where DNA samples are taken on any person arrested, whether they committed a crime or not, including demonstrators (or bystanders) in a political march.
FWIW ~20 US states do the same, this was ruled legal in 2013 (Maryland v. King, DNA collection is part of police booking procedure).
CODIS (the FBI's DNA database) contains more than 17 million non-forensic profiles[0], that's also >5% of the population.
But wait, there's more!
The Department of Defense's own DNA database (DoDSR) has more than 50 million records (collection started in the 80s and every applicant to a uniformed service gets included), and since the 2003 National Defense Authorization Act can be accessed by federal or military investigations for "the purpose of an investigation or prosecution of a felony, or any sexual offense, for which no other source of DNA information is reasonably available". So it can't currently be searched / "wild matched" against an unknown sample but if there's a suspect, a sample and no other DNA source then it's an option.
>The Department of Defense's own DNA database (DoDSR)
The reality of this is that it's just a big ass warehouse deep in the farmland of Virginia which houses unprocessed tubes of DNA. Its like the end of Raiders of the Lost Ark.
Sounds nefarious but it is actually a goldmine for genetics research.
As noted in the original comment, currently DoDSR can only be used for nominative sampling aka you have a name and want a known generic sample (and you have a federal or military judge allowing it). The limitations of the medium / storage means it can't practically be used beyond that.
The issue of false positives and false negatives is glaring in data sets of these sizes.
5% of France is about 3.3 million unique records.
From what I could see online, the false positive rates of various DNA tests are between 0.01%[0] and 40% [1]. Lets call it somewhere inbetween and say 20% are false positives, or 1 of 5 people.
This is just a lead in a case, sure, but that means that 1 out of 5 cases have false leads, wasting a lot of time and resources. I've no idea what the false positive rate for a 'normal' case is like, it could very easily be higher.
Granted, this is today's false positive rate, it should get a lot better over time. But to what percentage, and how long will that take?
Then you have the much more pressing issue of the false negative rate. I did not look too hard, but trying to find that rate wasn't simple. I've no idea what it is. In terms of DNA cases, you could then have a lot of potentially dangerous people falling through cracks in the system. Lets pull a number straight out of nowhere and say that the false negative and false postive rates are the same, about 20%. That would then mean that your odds of getting the 'right' criminal (specificity[2])are at about 80% and your odds of not getting the 'right' criminal (aka clearing people that are actually innocent, aka sensitivity ) are also 80%. Meaning that for any random crinimal case using the DNA database as a lead, you only have about a 64% chance of getting useful information out of the DNA database [3].
Serious crimes with DNA evidence can also triangulate suspects via finding their relatives in the database. Finding two second cousins from different sides of a suspect's family have a guy currently on trial for murder who had never been arrested, but whose DNA was found on a dead woman's body and clothes.
This seems like it would, if the trend continues, have some interesting ramifications for France's law forbidding parentage tests for men who suspect they may not be the father of a woman's child. The government may end up knowing more than the people in cases like these.
The national DNA database now includes over 5 percent of the population and it is a great tool for the police since the authors of serious crimes typically have almost always committed petty crimes before. It also means that you can solve small crimes like burglaries with DNA.
It is a bit worrying from a privacy protection point of view though. And I barely see this database ever questioned by the French press.