The history of same-sex marriage in Australia dates from its express prohibition by the Howard Government in 2004 to numerous subsequent attempts to legalise it at both Commonwealth and state/territory level, all of which have been unsuccessful as of 2016. Although the Australian Capital Territory did succeed in passing a same-sex marriage law in 2013, this was struck down by the High Court on the basis that federal laws prohibiting same-sex marriage would prevail over any inconsistent state or territory laws that allowed same-sex marriage.