Trying to hire a new worker. Own a local bar in the suburbs of New York. Guy who came in to work the kitchen said he served some time for having a "chopper and a co-op" and he believes he just ran into trouble because they couldn't tax it. He seemed like a down and out guy on the comeback, who got into a little white collar trouble, so I hired the guy, on the books. Now at the request of some other employees, I want to run a background check on him now. Can I do this after hiring someone?