1999: Timestamps Do Not Lie: the Software Trail That Caught Harold Shipman

Harold Shipman was a trusted family doctor in Hyde, England, who killed his patients with lethal injections of diamorphine and then falsified their medical records to make the deaths look natural. He often urged grieving families toward cremation, quietly destroying the evidence a post-mortem might have found.

What he did not understand was his own surgery computer. The practice software secretly time stamped every entry, and when investigators compared those hidden timestamps to the dates on his altered files, the lie was obvious: he had been rewriting patient histories after his victims were already dead. He went on trial in 1999 charged with just 15 murders, though he is believed to have killed close to 250 patients over more than two decades, making him Britain’s most prolific serial killer.

Shipman never confessed and maintained his innocence throughout the trial. He was convicted on all counts and later took his own life in prison.

A Serial Killers Computer Log tracked everything.
A Serial Killers Computer Log tracked everything.

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1944: The Acid Bath Murderer: John Haigh Dissolves His Former Boss in a Barrel of Sulphuric Acid

John Haigh, a convicted fraudster, murdered his former employer William ‘Mac’ McSwan and dissolved his body in a barrel of sulphuric acid. Haigh later claimed the killing was driven by a compulsion he called blood lust, but McSwan had money and property, and the murder looks less like madness than a calculated escalation of Haigh’s earlier fraud schemes.

Tellingly, whatever ‘compulsion’ Haigh described did not resurface until the cash from the McSwan killing had run out, suggesting the acid barrel was less about bloodlust and more about a ruthless, practical solution to funding his lifestyle.

Portrait of john george haigh - acid bath murderer. Public Domain.
Portrait of john george haigh – acid bath murderer. Public Domain.

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1998: The Forged Will That Exposed Britain’s Most Prolific Serial Killer, Doctor Harold Shipman

Harold Shipman was arrested on 7 September 1998 after police investigated the death of his patient Kathleen Grundy, who had left him £386,000 in a will that turned out to be forged. The clumsy fake unravelled quickly: a Brother typewriter matching the one used to produce the document was found in Shipman’s possession, and Grundy’s own family, alarmed that their mother would never have cut them out, had already raised suspicions with a solicitor.

The arrest opened the door to a far larger inquiry. Detectives uncovered a pattern of lethal diamorphine injections administered to elderly patients under his care, alongside falsified medical records designed to make the deaths look natural.

Shipman was eventually linked to the deaths of at least 215 patients over more than two decades, making him one of the most prolific serial killers in British history.

Last will and testament typed on aged paper with vintage typewriter
Last will and testament typed on aged paper with vintage typewriter

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1894: H. H. Holmes Kills Accomplice in Philadelphia Insurance Fraud Murder

On September 4, 1894, serial killer H. H. Holmes murdered his accomplice Benjamin Pitezel at 1326 Callowhill Street in Philadelphia. The original scheme called for Pitezel to fake his own death under the alias ‘B.F. Perry’, supposedly killed in a lab explosion, with Holmes supplying a substitute corpse so that Pitezel’s wife could collect a $10,000 life insurance policy. Instead, Holmes knocked Pitezel unconscious with chloroform and burned his body with benzene, staging the death as an accident.

A coroner’s jury returned a verdict of accidental death, and Pitezel’s body was buried in a potter’s field. Three weeks later, Holmes collected the $10,000 payout. The murder only unravelled after Philadelphia detective Frank Geyer investigated, ultimately exposing Holmes as one of the most prolific killers in American history.

Benjamin Pitezel; associate of H.H.Holmes
Benjamin Pitezel; associate of H.H.Holmes

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On This Day in True Crime History

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