If it's a 1-in-a-million chance of matching a random person, and there are ~7000 million people on the planet, on average this method will finger 7000 people fo

If it's a 1-in-a-million chance of matching a random person, and there are ~7000 million people on the planet, on average this method will finger 7000 people for each crime? Yeah, the 1-in-a-million number isn't quite right, but there are other reasons why DNA evidence isn't perfect. Twins and chimeras for a start. And then you go on to washing machines, which are great for spreading DNA from multiple sources all over lots of things that tend to get analysed in a forensics lab.