From 1995 to 1998 he was Secretary of the Australian Bill of Rights Group, and in 1998 joined Reform the Legal System.
[1] In 2014 Breen became an adviser to Senator Ricky Muir of the Australian Motoring Enthusiast Party but was sacked on 5 August 2014.
[3] He has campaigned over an alleged miscarriage of justice in the conviction of Stephen Wayne 'Shorty' Jamieson for the 1988 murder of Janine Balding.
[8] In the 2016 federal election the Renewable Energy Party fielded two senate candidates in each of New South Wales, Queensland, Tasmania, Victoria and Western Australia, and a total of eight candidates for the House of Representatives in Victoria (4), Tasmania (3) and New South Wales (1),[9] none of whom were elected.
[10] On 1 February 2018, the Australian Electoral Commission issued a notice that it was considering deregistering the party on the grounds that it had ceased to have at least 500 members.