"[7] However, by the following year Grimes' political stance had changed and he founded the pro-Brexit group BeLeave aimed at younger voters during the 2016 United Kingdom European Union membership referendum campaign.

[8] Grimes later dropped out of university, and between 2016 and 2018, he worked as a deputy editor for the political website BrexitCentral, founded by Matthew Elliott, the former Vote Leave chief executive.

[12] In May 2020 Grimes launched Reasoned, a website aimed at those "standing against the tide" who "hide [their] political views for fear of being called homophobic, a TERF, [or] racist".

[14] Facebook adverts for the group placed in 2018 were paid for by "Your Channel Media", a company owned and run by TPUK chief executive Oliver Anisfeld.

"[16] This prompted criticism, including condemnation by former Chancellor of the Exchequer Sajid Javid, and Grimes tweeted that "I reject in the strongest possible terms what Dr Starkey said in that clip and so very wish I'd caught it at the time.

The former director of public prosecutions Ken Macdonald called the investigation "deeply threatening of free speech",[17] a view which was echoed by some Conservative Party MPs.

[20] In 2018, Grimes was fined £20,000 by the Electoral Commission after it determined that there was evidence that BeLeave had spent more than £675,000 with the Canadian political consultancy firm AggregateIQ in coordination with the official Brexit campaign organisation Vote Leave in distribution targeted social media advertisements.

[citation needed] In October 2023, Byline Times published allegations against Grimes relating to "persistent sexual harassment of a junior straight male colleague" while working at GB News.