It's even worse than you think. The story that I heard had more details. The criminal DID NOT give away his DNA to a genealogy site.The police found DNA at the crime scene. They searched the genealogy site and found a close match to the DNA that belonged to a distant relative. The police then started knocking on doors of distant relatives until they had enough information to find the specific person. Then, they raided his trash can, and found the criminal's DNA.