In March 1971, William McMahon replaced Gorton as prime minister and Forbes was appointed Minister for Immigration, a title he held until the McMahon Government's defeat in the 1972 election. He resisted British pressure to admit ethnically-Asian refugees expelled from Uganda during Idi Amin's regime, stating "Applications by Asians in Uganda will continue to be considered on their individual merits in accordance with our non-European immigration policies. These policies reflect the firm and unshakeable determination of the Government to maintain a homogeneous society in Australia." Forbes also ordered the deportation of musician Joe Cocker in 1972, after a small quantity of cannabis was found by police in his Adelaide hotel room and he was charged with assault following a brawl at a Melbourne pub. In a 2014 interview Forbes stated that, while he accepted responsibility for the decision, he "didn't think it was necessary" and had been pressured by McMahon who believed it would be politically popular.