[5] His father was a prominent figure in Newfoundland and Labrador and Canadian politics, a provincial and federal cabinet minister who also served as Lieutenant-Governor of the province (2008–13).

The firm developed expertise in class actions, and Crosbie first came into the public eye as an advocate for breast cancer patients affected by delayed and erroneous test results[8] (settled in 2009, see Cameron Inquiry), for the victims of moose-vehicle accidents, for users of video lottery terminals, and for the former residents of residential schools in Labrador (settled in 2016).

[10] From an interest in helping injured children, Crosbie and his firm have given away thousands of bicycle helmets to young people across the province.

He has also volunteered with heritage organizations such as the Sealer's Memorial and Interpretation Centre in Elliston, Trinity Bay,[11] and worked with the Placentia Historical Society and the Town of Placentia to commemorate the 75th anniversary of the 1941 meeting of U.S. president Franklin D. Roosevelt and British prime minister Winston Churchill which established the Atlantic Charter.

[12] Crosbie's earliest involvement in politics came as a supporter of his father, who was a candidate for the leadership of the Progressive Conservative Party of Canada in 1983.

However, in 2015, his candidacy was rejected by the Conservative Party of Canada, reputedly as the result of his "playful barbs" concerning Prime Minister Stephen Harper in a Shakespearean-parody fundraising skit.

[14] In February 2017, Crosbie announced an exploratory candidacy for the leadership of the Progressive Conservative Party of Newfoundland and Labrador, following the resignation of leader and former premier Paul Davis.

[15] The leadership convention operated under a mixed vote-points system in which a hundred points were awarded in each of 40 districts across the provinces, based on the percentage of vote each candidate won.