https://amp.cnn.com/cnn/2018/06/02/us/golden-state-killer-unsealed-warrants/index.html
When the suspected Golden State Killer drove into a Hobby Lobby parking lot in April, investigators were waiting nearby. As he walked into the craft store, it gave them a perfect chance to collect a secret DNA sample.
Police swabbed the driver's side handle of [the suspect's] car, according to arrest and search warrants released Friday.
Authorities sent it for testing and matched it to semen recovered at some of the Golden State Killer's crime scenes, the arrest warrant said.
[...] The stop at the Hobby Lobby was just one of several ways investigators used to zero in on a suspect. Earlier this year, police tracked him down by comparing genetic profiles from genealogy websites to crime scene DNA, according to investigators.
On April 23, a day before his arrest, police say they collected multiple samples from a trash can outside DeAngelo's home in Citrus Heights, a town 16 miles northeast of Sacramento. They had watched the home for three days, the warrant said.
Previously: DNA From Genealogy Site Led to Capture of Golden State Killer Suspect
GEDmatch: "What If It Was Called Police Genealogy?"
(Score: 5, Insightful) by FatPhil on Monday June 04 2018, @03:19PM (9 children)
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 4, Informative) by AthanasiusKircher on Monday June 04 2018, @04:01PM (2 children)
Are you sure about that? The coverage I've read (admittedly not a lot) has implied this case was basically solely solved through DNA. And they went after the wrong people [washingtonpost.com] first, surreptitiously taking DNA in questionable ways:
That guy didn't pan out, so they tried a different online DNA database (from my link above):
So, yeah, there were "traditional investigative techniques" used after that, but it's unclear what all that entailed. It could have been as little as "Of relatives to this DNA match person, who lives near the attacks? Who's in the right age group?"
Then, it sounds like they went through his garbage, got some DNA. Then they swabbed his car at Hobby Lobby, and got a complete match.
To me, at least from the way it's been presented publicly so far, it sounds like 97% of the investigation was likely DNA-based. Sure, there will now be corroborating evidence (hopefully) based on things they figured out once they had an idea of who it was. But actually finding the "right guy" sounds like it was almost all based on DNA.
(Score: 3, Informative) by frojack on Monday June 04 2018, @06:34PM
Exactly.
But they had a complete semen DNA sample from back in the day. They had already been able to reduce the pool to specific racial profile, as well as other genetic markers. They weren't interested in huge swaths of the population by that point. So they submitted it to the DNA service INTENTIONALLY to gain a familial match, which is what this service specialized in. This was the only real "Hail Mary" play in the whole investigation.
Once you know it is a relative of a particular person (himself too young to be involved) you work outward from there.
Standard police work. Forget the Females, Eliminate the males one by one, wrong age, not present at the time, DNA already in (one of the) systems, already dead, already in custody, bats for the other team.
By this time you've probably got it down to less than 10. (swag).
Then start collecting DNA. Maybe you just ASK those you least suspect.
Maybe you dig through trash, watch for publicly discarded items.
I'd guess by that time you are down to two or three people.
There is a LOT of this case that is just dogged police work.
No, you are mistaken. I've always had this sig.
(Score: 2) by FatPhil on Monday June 04 2018, @09:24PM
But only one bit of that was the swab from the car.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by AthanasiusKircher on Monday June 04 2018, @04:14PM (5 children)
Also...
Agreed. At least, that's the way it should be.
The problem is -- juries don't tend to be very "reasonable," particularly when it comes to evaluating scientific evidence, and particularly when it involves statistics. And there have been a number of cases where convictions solely on the basis of DNA have had serious statistical errors in the way evidence was presented, leading to bad convinctions. Unfortunately, the public only tends to hear about the crazy cases where the police make severe blunders with DNA (e.g., it turns out that the supposed suspect has an ironclad alibi and was thousands of miles away).
Juries think of TV shows like CSI and assume when DNA comes into the picture, it must be rock-solid. It likely leads to quite a few innocent convictions each year, not to mention cases where DNA evidence is initially used for things like coercive interrogation that can generate a false confession -- which then can lead to a conviction even if the DNA evidence turns out to be inconclusive.
(I'm not saying any of this applies to the present case with the Golden State Killer -- only that in many cases lots of people often assume police do very diligent investigations, but the actual positive evidence for conviction can be surprisingly slim. Often it's just a "good story" that prosecutors make up to try to connect the dots...)
(Score: 2) by frojack on Monday June 04 2018, @06:42PM (4 children)
Name one.
Virtually all DNA based cases that have yielded wrongful convictions have been due to contamination of original crime seen collections, (accidental or intentional).
Statistical errors are virtually unheard of, because the Defense gets to have their own experts test the DNA as well.
DNA evidence exonerates far more people than it convicts.
No, you are mistaken. I've always had this sig.
(Score: 3, Interesting) by AthanasiusKircher on Tuesday June 05 2018, @02:28AM
First, I should be clear that what I meant was serious statistical misrepresentations in the way evidence was presented. Sometimes it's due to actual errors, but more often it's just playing off a jury's ignorance and when they hear "DNA match," they just assume it's ironclad.
There have been loads of coverage of the potential problems with this sort of thing in recent years. See articles about it here [sciencemag.org], here [theatlantic.com], here [innocenceproject.org], here [pbs.org], here [latimes.com]. And the FBI even admitted [usatoday.com] to a pattern of statistical errors in DNA calculations over 15 years. Granted, the magnitude of the FBI errors mentioned in the last link may have been small enough not to cause wrongful convictions, but if such errors could go overlooked for a long time, it's certainly likely that other estimates are sometimes off.
That's likely true, but we probably are significantly less likely to find out about wrongful convictions due to statistical error or misrepresentation, since usually it's significantly harder to challenge a ruling where a match was found. Evidence of contamination is a clear reason to challenge a ruling, but proving that a statistical misrepresentation (or even a blunder) had an effect on a jury is a lot harder.
If you're referred to ERRONEOUS cases, yes DNA is probably much more likely to be used to exonerate a bad conviction than to be used to erroneously convict. But again, part of the issue is that DNA evidence is seen by many juries (and judges) without nuance -- a "match" is a match, and so we just may not have gotten to a big wave of challenges yet because not enough judges are convinced to examine an appeal on this basis yet.
I'm not saying it's hugely widespread in leading to false convictions. But exaggeration of DNA matches has happened and is definitely a problem.
(Score: 3, Interesting) by AthanasiusKircher on Tuesday June 05 2018, @02:39AM (2 children)
I should also say there are a number of wrongful trials, investigations, and convictions buried in the links I gave (and things they link to), but if you want one piece focused on a specific wrongful conviction due to bad DNA stats, see here [gizmodo.com].
The link contains the following disturbing information concerning samples from crime scenes where there is a mixture of DNA:
That study was also mentioned in some of the links in my previous post. Lots of labs don't have adequate standards to deal with this sort of stuff or estimate potential error. Chances are there are quite a few bad convictions out there.
(Score: 2) by frojack on Tuesday June 05 2018, @07:45AM (1 child)
Again, made up tests. Fake situations.
Defense lawyers make mince meat out of those cases.
Defense lawyers hire their own labs. And labs are getting more plentiful to find.
No, you are mistaken. I've always had this sig.
(Score: 3, Touché) by AthanasiusKircher on Wednesday June 06 2018, @04:20AM
Did you even bother to look at ANY of the links? If you just look at the link in the post you replied to, there was a detailed discussion of a an actual case of an actual person who was convicted in basically just like this. You asked for me to name ONE case. There's one. Read. Learn. Stop being an ignorant ass. Then explore the manifold links in my previous post and see a multitude of other actual cases.