One of the two drummers for the Grateful Dead. He joined the Dead in 1967, but he left in 1971 due to the disgraceful actions of his father. Lenny Hart, his father, had stolen over $50,000 from the band using his position as the band's manager to steal it. In 1975, Mickey rejoined the band for good. He has worked on many solo projects after the band broke up in 1995 when Jerry Garcia died.
His best work with the Dead is probably the song "Drums," a drum solo by him and Bill Kreutzmann, with electrifying percussion.