Most people - and that includes most lawyers and judges, never mind the public - don't understand enough about scientific evidence to be able to assess it objectively. They also don't understand statistics. Tell someone there's a 100,000:1 chance of a DNA match, and they'll assume this is absolute proof of guilt, even though in a big city there will be 10-100 people equally likely to provide a match.

But I'm not sure you can apply the scientific method to law anyway. If you have a collection of evidence, it's hard to see how can you turn it into a hypothesis and then a firm prediction that will lead to a crime being solved.

Effectively a trial is a hypothesis - that a suspect is guilty. But it's not a prediction, except in the rather useless sense that you assume that if someone is imprisoned, a certain series of crimes will end.