Crewther then added a Graduate Diploma of Legal Practice, and two master's degrees in international law and diplomacy from the Australian National University,[3] the latter in which he was awarded the James Ingram AO Prize for Excellence in Diplomatic Studies for being top student.
[4] Professionally, Crewther has worked as an associate to then ACT Magistrate John Burns, as a lawyer in private practice, in policy and legal roles at the Commonwealth Department of Agriculture, in project management at AIATSIS, on the Port Curtis Coral Coast native title claim, as an international lawyer through the United Nations at the Kosovo Property Agency, as an adviser to former Minister for Veterans' Affairs (Victorian Liberal Senator the Hon.
[7] After a speech to parliament in late 2016, Crewther established the Parliamentary Friendship Group for Tourette syndrome as its founding chair.
He chaired the Sub-Committee's "Inquiry into establishing a Modern Slavery Act in Australia",[9] tabling the sub-committee's interim report in August 2017,[10] and the final report ("Hidden in Plain Sight") in December 2017,[11] which led to Australia's Modern Slavery Act 2018.
[2] In his inaugural speech to the Victorian Parliament, Crewther spoke of his opposition to vaccine mandates, and advocated for the decriminalisation of drug use and a "HECS-based system for [non-government] schools".
[23] In December 2022, Crewther was appointed as the Shadow Parliamentary Secretary for Justice and Corrections, and Liberal Party Whip in the Victorian Legislative Assembly.