Local drivers working after 14 hr clock

Got into a heated debate with my transportation manager today. I used my 16 hr big on Monday. I was off Wednesday but did not complete a 34 hr reset. Today I told my manager I was running out of time my 14 hrs burned at 6pm and he stated to get to the last stop and work until the relief driver arrived. Now the debate began when I told him I couldn't work past the 14 hrs workday at 6pm. He stated that I could drive the company van back. But I made the argument if something catastrophic happened (which probably wouldnt but for the sake of this scenario) and DOT was involved I would be the one in trouble for working past the 14 hr day. Now is my manager right or me?