[2] O'Brien is one of just 4 members of the 46th Parliament of Australia who did not graduate from high school, the others being Julie Collins, Jacqui Lambie and Terry Young.
[2] In his first speech in Parliament he spoke of his own decade long experience of living with posttraumatic stress disorder brought about while serving as a traffic accident investigator.
[9] After the retirement announcement of long serving Member of Wide Bay and Deputy Prime Minister Warren Truss, O'Brien was preselected for the 2016 federal election and won the seat.
[2] In 2016, O'Brien was also appointed as the Queensland Chair of the Federal Government's Black Spot Advisory Panel for 2016/17 by Minister for Infrastructure and Transport Darren Chester.
The challenge failed, and on 10 February O'Brien announced that he would no longer sit in the Nationals party room, but would remain a member of the LNP and continue to support the Morrison government.