Brown was ejected from the PC caucus on February 16, 2018, following reports that he was claiming he hadn't actually resigned as party leader and a series of Facebook posts in which he attacked the credibility of his accusers. Later that same day, Brown registered as a candidate for the Progressive Conservative leadership election, pending approval from the party, and on February 21, after being vetted, Brown was given the "green light" by the PC Party to run for the leadership.