Debs occupies a grim place in Australian criminal history, having been convicted of killing two police officers in a single incident — a crime that drew intense public attention and accelerated debate around officer safety. The murders spanned a period of roughly a year, beginning with the killing of a teenage girl in 1997 before culminating in the 1998 ambush. The sentences handed down — four consecutive life terms plus 27 years — reflect the scale of the court's response to what prosecutors presented as deliberate, premeditated violence.

A product of Prohibition-era organized crime, he built his reputation less through exceptional violence than through a carefully cultivated image — one that his wife Kathryn is said to have actively promoted. The 1933 kidnapping of Oklahoma oil businessman Charles Urschel brought him to national attention and ultimately to Alcatraz, making him one of the more recognizable names of the gangster era despite a career that rarely matched the legend.

His name became so synonymous with betrayal that "quisling" entered the English language as a common noun for traitor — a rare distinction that measures the depth of his legacy. What made him historically significant was less any personal ruthlessness than his willingness to lend a veneer of Norwegian legitimacy to a foreign occupation, heading a collaborationist government that served German administrative ends. His path to that role was not straightforward: he had earlier earned genuine international standing through humanitarian work and diplomatic service before turning toward fascism in the 1930s, founding a party that remained marginal until the Germans found him useful. He was executed by firing squad in October 1945, convicted of treason and war crimes.