Conrad Murray was released from Los Angeles jail at 12.01am local time yesterday after a change in California law allowed his time inside to be significantly cut.
The former cardiologist was convicted in 2011 of causing Jackson's death in June 2009 by providing the pop star with an overdose of the powerful anaesthetic propofol as a sleep aid. At the time Jackson was in the middle of preparing for a series of comeback concerts.
Murray's prospects are uncertain: At age 60 his licence to practise medicine has been suspended or revoked in three states and his face and name are well known due to his association with Jackson and his highly publicised involuntary manslaughter trial.
The former doctor is appealing against his conviction, although an appeals court has questioned whether it needs to hear the case.
His lawyer Valerie Wass has argued the court should not dismiss the appeal because it could alter his overall sentence and reduce some of the stigma his conviction has caused.
Despite being jailed, Murray has not been silent. Audio recordings of his calls have been posted on a celebrity website and the ex-doctor told a television show he cried tears of joy after a civil jury recently decided the promoters of Jackson's comeback shows did not negligently hire him.
He did not, however, give evidence in the civil case or during his criminal trial.
Murray previously maintained clinics in Houston and Las Vegas and frequently complained about conditions in jail after his conviction.
Ms Wass said Murray was looking forward to getting on with his life.