[3] In the 1980s, Linehan joined the staff of the Dublin politics and music magazine Hot Press, where he met his future writing partner, Arthur Mathews.

[20] In December 2024, Linehan announced plans to move to Arizona to work on a sitcom and create a production company with the comedians Rob Schneider and Andrew Doyle.

He also appeared in the pilot of Little Britain, as well as in series one, episode four, as a bystander who gets in the way of character Kenny Craig when he is attempting to hypnotise, from a distance, a man whose car he has crashed into.

He also appeared in series one, episode five, in which he played a journalist called Roy Sloan (from Whizzer and Chips) during a conference with Prime Minister Michael Stevens (Anthony Head).

The programme featured interviews with several of the UK's most successful television comedy writers and performers including Steve Coogan, Matt Lucas, David Walliams, Paul Whitehouse, Griff Rhys Jones and Ardal O'Hanlon, all of whom have worked with Linehan.

In 2011, Linehan appeared with several members of the cast in Channel 4's Father Ted Night, an evening of the writer's favourite episodes and two retrospective documentaries.

[25] Reviewing Tough Crowd in The Guardian, Fiona Sturges wrote that while Linehan's account of his comedy career has "verve and charm", the memoir "reads less like the story of a man heroically cleaving to his principles than a document of a peculiar and self-defeating obsession, a sad coda to a once towering talent".

[25] In a review in The Critic, Ben Sixsmith described Tough Crowd as "very entertaining" with "some valuable insights into comedy", but that Linehan "admits to losing his rag in a way that might not always be productive".

[26] In The Irish Times, Houman Barekat wrote that the memoir had "two distinct narratives", concluding that "Tough Crowd is a discomfiting read not because it contains hard-hitting home truths, but because its author clearly hasn’t worked through his issues".

[27] For The Spectator Debbie Hayton wrote that "This is a book of two halves" and that it "may well appeal to two completely different audiences", concluding that "if they want to understand the man they need to read it all.

[31] He began making anti-trans statements[clarification needed] online after the 2008 episode "The Speech" of The IT Crowd, written by Linehan, was widely criticised as transphobic and sexist.

[38] In 2018, Linehan praised anti-transgender protesters at that year's London Pride event who had carried banners and flyers saying that "transactivism erases lesbians", calling them "heroes".

[49] Following this interview, Eric Pickles, the United Kingdom Special Envoy for Post-Holocaust Issues, accused Linehan of trivialising the Holocaust.

[50] In January 2019, Linehan expressed concern over the news that Mermaids, a charitable advocacy organisation for transgender children and teenagers, was to receive a £500,000 lottery grant to open clinics around the United Kingdom.

[54][55] The same year, British journalist Dawn Foster accused Linehan and others of targeting a National Society for the Prevention of Cruelty to Children (NSPCC) employee who had been responsible for hiring model and activist Munroe Bergdorf, a transgender woman.

He used the account to call Colm O'Gorman "a traitor to women, gay people and yourself" for signing an open letter published by the Transgender Equality Network of Ireland.

[59] In February 2021, Linehan created a fake account on the lesbian dating app Her and publicly posted screenshots of non-binary people and trans women using it.

[60] In March 2021, Linehan gave oral evidence to the Communications and Digital Committee of the House of Lords on the subject of freedom of expression online, discussing his Twitter ban.

[19] Ahead of the 2022 Australian federal election in May, Linehan used his online platforms to rally international support for the Liberal Party candidate Katherine Deves, who had attracted controversy for anti-trans comments.

[62] In September 2022, Linehan said that his anti-transgender activism had led him to question the safety of COVID-19 vaccinations and the scientific consensus on climate change "because I've been lied to so conclusively by all the people I used to trust".

[63] In interviews in 2022 and 2023, Linehan said the debate over transgender issues had "consumed his life": it had lost him work, made him financially destitute, and ended his marriage.

[68] In April 2023, Linehan was again banned from Twitter, following his appearance at an anti-trans event called Let Women Speak in Belfast, Northern Ireland.

He had tweeted the words "Durr imm gonna kill em" in response to a Twitter user who referenced counter-protestors at the Belfast event.

[73] In August, during the Edinburgh Festival Fringe, Linehan and other comedians performed a stand-up comedy show outside the Scottish Parliament after his original venues cancelled his booking over his views.

[75] On 12 November 2023, he appeared on This Week on Ireland's national radio station, RTÉ, to talk about his claim of being cancelled, defend his anti-trans activism, and to promote his memoir Tough Crowd.

The couple revealed their decision for Helen to abort a foetus with acrania while living in England in 2004, and their discovery that undergoing the procedure in Ireland would have been an offence carrying a maximum 14-year prison sentence.