qnli question: In what year was the first Aboriginal Senator elected? sentence: Historically, Liberal Governments have been responsible for the carriage of a number of notable "socially liberal" reforms, including the opening of Australia to multiethnic immigration under Menzies and Harold Holt; Holt's 1967 Referendum on Aboriginal Rights; Sir John Gorton's support for cinema and the arts; selection of the first Aboriginal Senator, Neville Bonner, in 1971; and Malcolm Fraser's Aboriginal Land Rights Act 1976.