Can you be denied insurance coverage because of a PJC on your driving record thats more than 3 years old.?

My wife just got selected for a job in NC with our local paid EMS. They selected her but said there insurance company wouldn't cover her because of a PJC from 2003. PJC's go away every 3 years its been 4. Insurace companys cant use PJC's to raise rates and PJC are off your driving record at the DMV and insurance aftrer 3 years. So can they legally deny her coverage for that? Its on her permanent record like any one else with a PJC but its not a moving violation! Its just there for records thats it. The company driving policy she meets whats up with the insurance. I think this is illegal after 3 years. Does any one know?