The criminal past of an individual can be found through many different sources.  You can find court records very easily through the Internet at no cost in most cases.  If you have the right information including complete name, birth date and birth location, and current address and past addresses for about the last three years, you are most likely to have success in your attempt to find any court documents related to that individual.  This is considered public information and is therefore open to the general public.  You can find this information from many different sources and sites online and from state government sites as well.