Patrick Carraher was born in 1906 in the Gorbals area of Glasgow, Scotland, into a respectable working-class family. Despite his upbringing, he developed a penchant for violence early on, leading to his first incarceration in a borstal at the age of 14. Carraher's life became a cycle of imprisonment and release, with his violent tendencies exacerbated by a serious alcohol addiction. 

He became a prominent figure during the era of Glasgow's razor gangs, known for his love of fighting and his skill with blades. Unlike others who engaged in crime for profit, Carraher seemed driven by a desire for violence itself. His time in prison only hardened him, as he thrived in the brutal environment where knife fights were common. Alcohol often fueled his aggression, making him a dangerous presence both inside and outside prison walls.​

On August 13, 1934, Carraher fatally stabbed James Shaw, a soldier, during a drunken altercation in Glasgow. At his trial, he claimed he was too intoxicated to understand his actions, leading to a conviction for culpable homicide (manslaughter) rather than murder. He was sentenced to three years in prison, a verdict that surprised many in the legal community. After his release, Carraher continued his violent behavior, including charges of razor slashing and assault in 1943.​

His final act of violence occurred on November 23, 1945, when he murdered another soldier, John Gordon, during a drunken confrontation. Carraher, seeking to settle a dispute involving his friend Daniel Bonnar, attacked Gordon with a sharp chisel, stabbing him in the neck. Gordon died shortly after the attack. Carraher was arrested, and during his trial in February 1946, both Bonnar and Carraher's girlfriend testified against him. The jury deliberated for only twenty minutes before finding him guilty of murder. He was executed by hanging at HM Prison Barlinnie on April 6, 1946, by executioner Thomas Pierrepoint.