> if the crime is minor or irrelevant, the record won't hurt the person, otherwise it's a proof that it's not as irrelevant as you think

Let me tell you a little thing called marijuana possession charges and how they make students ineligible for student aid and government loans/grants. Even getting charged with possession of a single joint is enough to bar a student from receiving aid or loans. Such charges or convictions are the reason employers turn people away all of the time.