New Zealand expat Bevan Forsythe has lost his appeal against convictions for murder and attempted murder.
In 2010, he gunned down father and Beerwah real estate agent Brent Dumper, during a housewarming party at Upper Coomera.
The victim was shot in the back at point blank range in front of his family.
Forsythe then fired the pump-action shotgun at another guest, who pushed it away, escaping serious injury.
Three judges agreed, there was no miscarriage of justice, and dismissed the appeal.
