During Abbott's prime ministership, Australian law continued to define marriage as a union of a man and a woman, while recognising same-sex couples as de facto couples in areas such as taxation law, social security law, immigration and superannuation, and Abbott did not support changing the law. During Abbott's time as Opposition Leader and Prime Minister, the position of the Labor Party and opinion polls shifted towards favouring same-sex marriage. Abbott determined that a national plebiscite, rather than a Parliamentary vote should settle the issue. The Turnbull Government retained this policy.