A conviction stays on your record forever, unless you receive a pardon (i.e., it is truly expunged.) Even if your case is later dismissed, the conviction will still show on your record, along with the dismissal.
Question is unclear. Are you asking how long the record of your conviction will remain on file? If so, unless you committed the offense prior to your 18th birthday, a conviction is a permanent record in your adult criminal history record.
A conviction of minor in possession in Michigan is a criminal conviction and stays on a person's record forever in Michigan. The only way it won't is if there is a successful motion to set aside the conviction.
A Federal Conviction stays on your record forever, but if the conviction is over 15 years old, it can't be used against you in a future proceeding to determine criminal history. Larry Levine Owner www.americanprisonconsultants.com
If the person is an adult a misdemeanor conviction can be a permanent part of his or her criminal record. In most US states it is usually possible to have a low class misdemeanor conviction removed from a record for employment issues.
Any conviction of a misdemeanor or felony after your 18th birthday will result in an entry on your criminal history record. In the UK, all convictions will count as part of your criminal record, regardless of your age at the time of conviction.