The major (mis)uses would be faulty forensics where from human mistake, computer error, equipment failure, hash collision, procedural failure, or manufactured e

The major (mis)uses would be faulty forensics where from human mistake, computer error, equipment failure, hash collision, procedural failure, or manufactured evidence. If the law is sane then there is safeguards that require independent proof of evidence beyond that of DNA, but in cases where they are desperate enough to go to genealogy databases there tend to be a major lack of independent evidence beyond of DNA.