A judgment of conviction can be vacated and deemed not to exist upon successful completion of a period of probation with suspended sentence. 6 CMC § 4113(k). (Cannot link directly to statutes.)
Upon successful completion of the probation period, the Office of Adult Probation shall file a motion to set aside conviction. The prosecutor has 20 days to object. For the specific procedure, see 6 CMC § 4113(k).