Criminal History

How long will a misdemeanor stay on your record?  If trying to get a job and a criminal record check finds a drug possession misdemeanor on your history, can it and will it affect the likelihood of employment?  Will it ever disappear?  How long, legally, can potential employers view your history?
A criminal record is forever.  Only an expunction or pardon removes a criminal conviction.  In North Carolina a person who was convicted of a misdemeanor before age 18 could be eligible for an expunction.  Pardons can only be granted by a governor or the president.
It is up to each individual employer to decide whether to hire someone with a criminal conviction.  There is no limit on how far back an employer can look into your past.