Operating across Moscow Oblast during the final years of the Soviet Union, Ryakhovsky killed 19 people over a five-year span that included elderly men and women, teenagers, and men he targeted based on sexual orientation. His crimes escalated markedly in their violence over time, and his cooperation with investigators following his 1993 arrest produced a detailed record of the killings. The case unfolded against the backdrop of a state in political collapse, a context Ryakhovsky attempted to exploit when he sought clemency during the constitutional crisis of that same year.

His place in the record is secured less by any single act than by the accumulation of grim details: a minor functionary of the British state's execution apparatus who assisted in twenty hangings, including the hanging of a man later established to be innocent. Dernley's career as an assistant executioner was unremarkable by the standards of the role, but the circumstances surrounding his removal — a conviction for publishing obscene material — offered a window into the character behind the official function.