Do I have to disclose my case disposition or any details about it like my arrest to any police agencies?

I had a gun position case which was dismissed and remanded back to the grand jury which was then no billed. The arrest and finger prints are in the process of expungemnt now. However, I am interested in a career with the NJ State Troopers and I dont want to be judged based upon the unfortunate situationed that happened.