He was the director of the Centre for Investigative Journalism (CIJ) at Goldsmiths, University of London; Co-Founder with Eileen Chubb of the UK whistleblower support group, The Whistler; and a Trustee of the Courage Foundation.
MacFadyen has appeared in a number of documentaries about Wikileaks, including We Steal Secrets and Julian Assange: A Modern Day Hero?
He went on to report from the Nicaraguan Revolution, a war between the right-wing Contras and the Marxist Sandinista National Liberation Front in the 1980s,[7] and Iran-Contra, neo-Nazi violence, Watergate, the history of CIA.
[8] MacFadyen had produced and directed more than 50 documentaries since the 1970s many for Granada Television’s World In Action,[9] investigating a diverse range of topics that includes industrial accidents, neo-Nazi violence in the UK, Chinese criminal societies, the history of the CIA, Watergate, election fraud in Guyana, the Iraq arms trade, child labour, nuclear proliferation, and Frank Sinatra's connection to organised crime.
[13] In April 2003 MacFadyen co-founded with Michael Gillard the Centre for Investigative Journalism (CIJ) as a non-profit organisation to address the worsening media climate for in-depth, sceptical and adversarial reporting.
MacFadyen helped form the Julian Assange Defense Committee along with his wife Susan Benn and the journalist John Pilger.
[20] When MacFadyen died, Assange asked to be allowed to temporarily leave his asylum in the Ecuadorian embassy to attend the funeral, but the request was denied by Sweden's Attorney General Anders Perklev.