I know of a couple of options and they apply at least here in Virginia. Any member of the court is tied in to the data base, which is better than shifting through court records. So if you have a friend that is an attorney you could get them to look legally. Plus any conviction someone has is a matter of public record unless they were a juvenile, so you have the right to go look in the court records, most are now online. Beyond that you are looking for other things, I only know of private services that do charge quite a bit. My wife works with a charity dealing with kids and they pay a reduced rate of $5,000 per person, so I can only imagine what a private citizen would have too. Since you are needing to do this I can imagine that you have serious concern and wish you the best.