It's easy to imagine a world where if they find someone that's likely a first (or second!) cousin of a rapist, that they then surveil the entire family and use that as evidence for warrants or other investigative tactics. In this case they cross referenced the familial identification with other factors, but imagine if they hadn't? They might have put a tail on everyone who shares a common grandparent or great-grandparent.
Ethically: law enforcement finds most violations of the law in places they look, so if it's unfair where they're looking, it's easy for that to translate into unfair outcomes. A society where police are watching every Capulet but not investigating the Montagues is one where most of the arrests will be of Capulets, regardless of who is actually committing crimes.
Therefore, when talking in populations, surveillance approximates punishment and familial surveillance approximates collective punishment of an extended family.
If you run a 99.99% accurate match against a database with 100,000 people, one of whom is the criminal, you are going to get 10 false positives.
If you're one of those false positives, good luck convincing a jury that the 99.99% accurate test is wrong in your case. There's a reason for why general warrants, and most kinds of fishing expeditions are illegal.
More likely, though, they will get a full confession. Serial killers often love to explain their work and take a lot of pride in confessing, because they're really messed up people.
In this case, an man in Oregon was earlier a suspect, but direct DNA comparison ruled him out.
As a result your DNA can be found at a location you have never been to.
If DNA evidence is being used to narrow down a small group of suspects this is less of a problem than if you are searching a population scale group.
Sure, but how could it possibly be linked to you?
You argue that a judge could issue a warrant on an innocent person. However, warrants are only issued if there is enough plausibility that a person could be guilty of a crime. At the point the warrant is issued, the government can now force you to give your DNA. But that could happen right now.
Ultimately, in this case, the FBI barely exercised any of their authority. They didn't do any backroom dealings or use 'secret' laws. They just signed up to a genealogy website where people freely share their DNA information with the DNA sample voluntarily given to them by a rapist and murderer. The rapist has no right to any kind of privacy after giving his DNA away. Moreover, no one has any right to prevent a person who shares their genetic information from not disclosing it.
Because your cousin was arrested in 1999 for burglary and held for 30 hours until they realized they had the wrong guy.
That is exactly what the article is about: using large genetic databases to find DNA they have never collected in connection to an investigation.
What this means is that getting just a small fraction of the population into this database will enable it to provide leads for any DNA sample.
Umm...
The person who shared their DNA was neither a rapist or murderer but was simply related to one.
You already exist in a criminal database, comes up as a hit, police create a narrative to fit it, even though it is a false narrative.