La Rooij joined Jim Anerton’s New Labour Party in 1989, while still only 17 or 18. He stood for Parliament for the NLP in 1990 in the conservative Southland seat of Wallace. At one point he was Otago District secretary of the NLP, but resigned, along with his comrade, John Andrew Zwingle Moore, in 1992, when the NLP joined the Alliance.
At Otago Uni, La Rooij was a leading member of the campus Marxist club, “Progressive Left”, as was John Moore.
By 1993, La Rooij was studying at Vic and was an active member of the Victoria University “Bolshevik Club”. The VUBC was affiliated to Bill Logan’s Wellington based, Trotskyite sectlet, the “Permanent Revolution Group”, which in turn was part of the “International Bolshevik Tendency”. La Rooij was with the Bolsheviks for several years and at one point was their spokesman.
La Rooij’s friend, John Moore, was also in the VUBC and was still supporting the “International Bolshevik Tendency as late as 2001.
In 1994, La Rooij was VUWSA Campaign co-ordinator, with the job of organising demos, protests, sit-ins, occupations and other “revolutionary” activity. In 1996 he spoke at a Vic Uni meeting against allowing a policeman to be based on campus. In 1997 he addressed a protest at Parliament where 70 students were arrested.
In 1998 La Rooij finished his MA History Thesis on “Anti Semitism and the Far Right in NZ 1929-47”. He has maintained an interest in the subject and has published several articles. His latest, in January this year, in “Labour History”, was entitled “Arthur Nelson Field : Kiwi Theoretician of the Australian Radical Right?”
By 2001, La Rooij was a researcher for the Waitangi Tribunal. Currently he is Research Team Manager for the Crown Forestry Rental Trust. The CFRT is charged with researching and funding maori land claims, so La Rooij’s position is a very important and influential one.