Yup.
Forensic genealogy based on genealogy websites is a hugely controversial issue in terms of ethics and consent but is solving many, many cases. DNA evidence isn't indisputable proof however but it usually good enough to prove beyond reasonable doubt.
The Golden Gate killer, Joseph DeAngelo in the US was identified using DNA forensic genealogy.
He is an ex-Police officer who had ceased his raping and murders for many years before he was arrested as an elderly man. Proving, along with Dennis Rader and others, that the previous psychological and criminal profiling statements of 'fact' that serial offenders would not stop unless forced to by prison or death, to be bollocks.
With Joseph DeAngolo, the Golden State killer, in the years when he wax raping and murdering and not thinking for a second that DNA would be a 'thing' he left DNA at numerical crime scenes.And the police didn't even know about DNA till it became a 'thing'.
But DNA only means something if you have a match. For years after the advent of DNA evidence, the Police were using the DNA profile to match against any profiles in the criminal justice system of individuals arrested or incarcerated. No match.
So some forensic genealogists put his DNA profile into genealogy sites who include that data and don't have a policy to restrict law enforcement from using that data (a lot of sites won't assist law enforcement).
So they found a DNA match to however many × cousin to other people on the genealogy site so they could say "the person who raped/killed this victim shares this % of DNA with this person on this site so they are related
Then you work on the family trees to find the most likely person and in DeAngolos case,a Judge felt the genetic evidence was compelling enough for the Police to monitor him and covertly gain a DNA sample. Which they did from a tissue and his car door handle.
That DNA sample giving an extremely low liklihood when compared to DNA from the original crimes, that any other person in the world could have committed them.
After arrest aged 73, he made some kind of confession that he committed the rapes and murders while under the influence of an 'alter personality'. With no evidence being assessed by psychiatrists that assessed him that he was suffering from a disassociate personality disorder.
His defence team also suggested he may be suffering from Alzheimers and he looked confused being wheeled into court in a wheelchair.
In-cell CCTV recording documented him working out on his cell lifting water bottles as weights and doing press-ups and pull-ups unusual for a man of his age.