They're probably not erased after a few years; these records have already been used for criminal investigations. Considering their utility, I'd be surprised if

They're probably not erased after a few years; these records have already been used for criminal investigations. Considering their utility, I'd be surprised if they were erased. There are a few cases in the news; here's the first one that popped up on my search engine: https://en.wikipedia.org/wiki/Melanie_McGuire https://en.wikipedia.org/wiki/Melanie_McGuire