Poison has long been the weapon of choice for those seeking to kill discreetly. Its silent, often undetectable nature allows perpetrators to commit horrific acts while leaving investigators puzzled. From Victorian England’s arsenic laced crimes to modern day poisonings carried out in hospitals, these cases have left an indelible mark on criminal history. Advances in forensic toxicology have played a crucial role in exposing the criminals behind these acts, but even today, poison remains a chilling method of murder. In this three part series, I explore 20 notorious cases, each with its own unique and haunting story.
Part 1: Historical Poisoners
Mary Ann Cotton: The Victorian Serial Killer (1832-1873) Mary Ann Cotton is widely regarded as Britain’s first female serial killer. Over the course of two decades, she murdered at least 21 people, including her husbands, children, and lovers, all to collect life insurance payouts. Cotton relied on arsenic, a tasteless and odorless poison that was readily available in Victorian England. The symptoms of arsenic poisoning often mimicked cholera or other common illnesses of the time, allowing her crimes to go undetected for years.
Cotton was eventually caught after the suspicious death of her stepson, Charles Edward Cotton. An autopsy revealed traces of arsenic in his system, leading to her arrest. During her trial, Cotton denied the charges, but the evidence against her was overwhelming. She was convicted of murder and hanged at Durham County Gaol in 1873. Mary Ann Cotton remains one of the most infamous poisoners in history, her name synonymous with greed and betrayal.
Catherine Flannagan and Margaret Higgins: The Black Widows of Liverpool (1884) Catherine Flannagan and Margaret Higgins, sisters living in Liverpool, England, became known as “The Black Widows” for their cold blooded murders of family members and lodgers. Their crimes spanned several years in the 1880s and were motivated by greed, as they sought to collect life insurance payouts under the then popular “burial club” system.
The sisters used arsenic, a poison readily available at the time, to kill their victims. Arsenic poisoning often mimicked symptoms of natural illnesses, such as gastric ailments, allowing their crimes to go unnoticed initially. They targeted family members, including Margaret’s son, as well as tenants who lived in their home.
Suspicion arose after the death of a lodger, whose insurance payout was traced to Margaret. An investigation revealed a string of suspicious deaths, and authorities exhumed several victims, finding arsenic in their remains. Both women were arrested and convicted of multiple murders. In 1884, Catherine and Margaret were hanged at Kirkdale Gaol in Liverpool.
Nanny Doss: The Giggling Granny (1920s-1954) Nanny Doss, infamously known as “The Giggling Granny,” was an American serial killer responsible for the deaths of at least 11 family members, including her husbands, children, grandchildren, and in-laws. Born Nancy Hazel, Doss began her killing spree in the 1920s and continued for over three decades.
Her weapon of choice was arsenic, which she mixed into food and drinks. Doss often claimed her victims' deaths were accidental or due to natural causes, allowing her to evade suspicion for years. She gained the nickname "The Giggling Granny" because of her cheerful demeanor and tendency to giggle during her confessions.
Doss’s crimes came to light in 1954 after the death of her fifth husband, Samuel Doss. An autopsy revealed arsenic poisoning, leading to her arrest. She confessed to multiple murders, claiming her motives ranged from financial gain through life insurance policies to dissatisfaction with her relationships. Nanny Doss was sentenced to life imprisonment in 1955 and died of leukemia in 1965.
Stay tuned for Part 2 of this series, which will be posted next Saturday.
