Brown was involved in the right-wing Conservative circles including the Monday Club and the Eldon League. Brown was a founding member of the No Turning Back group which included Michael Portillo, Peter Lilley and Neil Hamilton. Brown regarded Portillo as one of his closest friends in the early years of the 1980s claiming, "we hit it off right away." He accompanied Portillo on holidays with other friends including Laud.
During his parliamentary career, Andrew Roth's Parliamentary Profiles described Brown as "an assiduous free tripper who repays his hosts". During the Cash for Questions parliamentary scandal, Brown admitted to, and apologised for, accepting money to lobby on behalf of US Tobacco without declaring it. He was alleged to have received £6,000 from Ian Greer Associates to lobby on behalf of US Tobacco, and to have failed to declare it in the Register of Members' Interests or to ministers. He was further alleged to have not declared the income from Ian Greer Associates until the payments became publicly known. The Parliamentary investigation found that Brown failed to register an introduction payment from Mr Greer on behalf of US Tobacco and that he "persistently and deliberately" failed to declare an interest in Skoal Bandits in his dealings with ministers over the issue. He did not immediately declare the payment to the Inland Revenue. Mr Brown also received a free flight to Connecticut to be briefed by the company, which he did record in the Register of Members' Interests.
Resignation
Brown resigned in May 1994 after The News of the World published pictures of him on holiday in Barbados with a 20-year-old gay man. At the time, the age of consent for homosexual activity was 21, so the paper ran the story under the headline "Lawmaker as lawbreaker". After resigning, Brown subsequently acknowledged his homosexuality. The media linked Brown's resignation to Prime Minister John Major's ill-fated Back to Basics campaign.
After Westminster
Brown lost the election for the new Cleethorpes seat at the general election on 1 May 1997. Initially he struggled to find employment, working for David Evans’contract cleaning firm. In April 1998 he submitted a piece for The Independent on how he was looking forward to being canvassed by the Labour Party candidates for his area in the Westminster City Council elections, which would give him an opportunity to play the kind of tricks voters often play on election candidates. The piece was published and was well received. It led to a regular commission as a political sketchwriter for The Independent starting in 1999, as well as political commentary for other newspapers. Today he regularly appears as a commentator and newspaper reviewer on British television, particularly on BBC News 24 and Sky News. He joined Nigel Farage's Brexit Party in April 2019 but said that he is not planning on contesting elections.