How can the Masters allow Angel Cabrera back?

"Cabrera, who won the U.S. Open at Oakmont in 2007 and the Masters in a playoff in 2009, was imprisoned for two years for assaulting, threatening and harassing Cecilia Torres Mana, his partner of two years. Her case was joined by that of another former partner, Micaela Escudero"

Why allow him back?