Thomas Griffin, Assistant Gold Commissioner on the Queensland goldfields, was entrusted with accompanying a shipment of money from Rockhampton alongside police troopers John Power and Patrick Cahill. The two troopers, childhood friends from Ireland who had joined the Queensland police together, had no reason to suspect that the official travelling with them intended to steal the money and kill them. Before departure, Power had noticed something suspicious about the escort bags and insisted Griffin reseal them, a precaution that would later help establish his guilt. Griffin had already interfered with the shipment, and the two policemen stood between him and the money. When the party camped beside the Mackenzie River, Griffin drugged the troopers' tea with a narcotic. Once they were asleep, he shot each man in the head in the early hours of 6 November 1867, then burned the parcel wrappings in the campfire to conceal evidence of the theft. When the bodies were discovered days later, Griffin told a startled bank manager, "they are shot, you will see if they are not." His suspicious behaviour eventually drew police attention. Investigators secretly dampened his revolver to prevent him from using it and placed him under arrest. Griffin denied the murders at trial but was convicted and sentenced to death. In the weeks before his execution, he attempted to bargain for his life by revealing where he had buried the stolen banknotes, admitting his involvement in the killings in the process.
