I think it can depend on where he lives. In California it is 7 years, but 2 years for marijuana offence. The 7 years can end up being longer if the person was on probation and violated – then the 7 years count can start again from the violation date.
My employer will hire persons with convictions, but it is on a case by case basis, the head of HR and the CEO have to authorize it, and the conviction must have been disclosed on the initial employment application. If it wasn’t on the application and it comes back during the background screen, it is an automatic “no hire.”
I have discovered something with the background screens, and this was true for 3 different screening companies we used: if the applicant had no record of residency or earnings in a county then their conviction in that county didn’t show up.