Byrne was born in Sydney and was educated at St Martin's Catholic Primary School and Villanova College in Brisbane.
He initially entered the Augustinian seminary and became a friar for five years, but later studied teaching at the University of Queensland.
[1] He caused particular controversy when, in 1974, he asked in Parliament why earlier recommendations of an investigating police officer to charge then-Labor Senate nominee Mal Colston with arson had not been acted upon.
Rae Wear notes in her biography of Bjelke-Petersen that Byrne received 'very bad publicity' over the incident.
[1] Byrne worked as a history master at San Sisto College in Brisbane before his election and as a lecturer at the Queensland Police Academy after leaving politics.