Hepnarová's case is notable for the deliberateness behind it: months of planning, a rehearsal run on the day of the attack, and letters sent to newspapers explaining her intent before the victims had even been identified. She framed the killings not as a breakdown but as a verdict — a calculated act of retribution against a world she believed had persecuted her. The attack on a tram stop in Prague in 1973, which killed eight people, remains one of the most premeditated mass casualty events carried out by a single individual in Czech history.

Over a six-week span in late 1998, Harris carried out three killings in and around a regional New South Wales city, crimes serious enough to earn consecutive life sentences without parole. The compressed timeframe and the severity of the judicial outcome mark him as one of Australia's more consequential cases of serial violence outside the major metropolitan centers.

His position within the Mariupol police force gave him both the tools and the cover to operate undetected across nearly four years, during which he confessed to nineteen killings. The fact that the perpetrator was an officer of the law rather than someone the law was hunting shaped the particular nature of this case and its aftermath.