I’m certain that my daughter is dating someone with a checkered past. I am concerned. How do I find criminal records on someone?

Everytime I look up where it says free, it always ends up costing something. Is there any site where you can actually get info for free? Otherwise, what is the best most accurate website to go to to obtain possible arrest or criminal records of a person?

I’m trying to find out what percentage of pro athletes have criminal records. Also, the percentage that have felony convictions.