Jurors have found Michael Slater, 73, guilty of sexual assault in a case that dates back to the 1960's on Canadian Forces Base Uplands.
The 53-year-old victim in the case cannot be named because of a publication ban.
He alleged he'd been raped by his teacher when he was 13 years old and a student at Elizabeth Park, a school run by National Defence, between 1968 and 1970.
Slater was found guilty Saturday morning of indecent assault, gross indecency and buggery relating to this victim and one other.
He will be in custody until he is sentenced on May 15.