Pardon or expungement for felon Criminal Records, Expungement

My nephew now 27 yrs old was 18 at the time of his accident. He and friends had sniffed from air can, 3hrs later he passed out while driving injuring backseat passenger. He admitted what he had done even though nothing showed in his system. He served time in jail and probation with excellent behavior. He is not a violent threat to society. He has not been in trouble since- perfectly clean record. But unfortunately the felony is on his record and he cannot move forward with a job and or his life no matter how hard he tries. He tried for govenor pardon but only so many were received ; his was not. How is he supposed to move on and have a second chance if the doors keep slamming?