[7] In March 1998 Marr was among the first to be arrested at what proved to be a several-months long, but ultimately successful, protest against uranium mining at Jabiluka in the Northern Territory.
[14] However, Marr's leadership in the campaign against Gunns resulted in two separate writs brought in the Supreme Court of Victoria.
Marr was named as the lead defendant among 14 others in a claim alleging interference in the practices of Gunns Ltd in six separate incidents.
[18][19] By the end of 2009 Lyndon Schnieders had failed in his bid to become appointed as the Wilderness Society's National Campaigns Director after an international applicant was chosen for the position.
[20] Imminently following the staffing decision, Marr claimed he was in a power struggle with Schnieders and chaos enveloped the Society.
[22] In September 2010, Marr's resignation was forced by an extradentary general meeting of the Wilderness Society held in Adelaide.
Negotiating on their behalf, Marr convinced the new management at Gunns to sell to Wood and Cameron, who purchased the mill for around $10 million.
In July 2014 Tasmanian media published a refutation by Marr of accusations that he had been installed with the express intention of sabotaging the plant as reported in an article in the Monthly.
Marr's work centres around lobbying of the UNESCO World Heritage Committee on the proposed raising of the Warragamba Dam wall.