recent arrest

My son was arrested for hitting a man on a bus. We live in Colorado and this is a first time offense. Need help on what to do? what could happen?

I am a law school graduate. What I offer is mere information, not to be construed as forming an attorney client relationship.

PART 2
ASSAULTS

18-3-201. Definitions.
18-3-202. Assault in the first degree.
18-3-203. Assault in the second degree.
18-3-204. Assault in the third degree.
18-3-205. Vehicular assault.
18-3-206. Menacing.
18-3-207. Criminal extortion - aggravated extortion.
18-3-208. Reckless endangerment.
18-3-209. Assault on the elderly or persons with disabilities - legislative declaration. (Repealed)
http://www.leg.state.co.us/inetcrs.nsf/revstat?OpenView&Start=18.302&Count=30&Expand=18#18