The Gossip Girl actor was arrested in Plano, TX in June 2010 when police found 2oz of marijuana during a body search.
Crawford cut a plea deal with the authorities, where he agreed to meet with a probation officer once a month and perform community service.
A Texas judge erased the drug arrest from Crawford's record on Tuesday upon the actor's completion of 80 hours of community service.
Crawford worked in a church and helped out a local hospital in order to fulfil his commitment.
The star could have faced up to six months in jail if convicted of misdemeanour marijuana possession.
Crawford has signed on to co-star with Cameron Diaz and Jennifer Lopez in the upcoming film What to Expect When You're Expecting, which is to open on May 11, 2012.
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