A jury of seven women and five men in the High Court at Christchurch took just two hours to find McLaughlin guilty of murdering his ex-partner's daughter on November 10, 2011.
The 35-year-old had denied strangling the schoolgirl with a piece of cord, stuffing socks in her mouth, dousing her house in petrol and setting it ablaze.
The jury weren't allowed to know McLaughlin's criminal history.
In Australia in 1995, Mclaughlin bashed 14-year-old Phillip Vidot with a cricket bat, while a mate ran him over in a car.
Vidot died, and Mclaughlin was sentenced to 12 years in jail for manslaughter but after just four years he was deported to his native New Zealand in 2001.