First, you have to report any

arrest even it relates to traffic violation. Second you have to report any citations other than traffic violation.(read 485 form carefully) I do not know what will be revealed during FBI fingerprint check, name check. The consequence is that if they later found anything that you did not report you may be in big trouble. However, INS ususally only care about arrest. People still got their GC even commiting petty crime such as small shoplift.