John Taylor was born on 27 August 1956 in Leeds, West Riding of Yorkshire, England. He spent most of his adult life living in the Bramley area of Leeds and worked as a parcel delivery man for Parcelforce, a subsidiary of the Royal Mail. Known locally as "the pet man," Taylor kept several animals, including dogs and ferrets, and sold pet food in his community. He also had a reputation as a poacher, often venturing into nearby woods to hunt rabbits. To those who knew him, Taylor appeared to be an unremarkable, quiet man; his neighbors considered him trustworthy and ordinary, with no overt signs of danger.

His criminal history, prior to his eventual exposure as a rapist and killer, was limited to a single conviction for the theft of a suit at the age of 15. Taylor lived alone after his divorce in 1996 and was a habitual user of lonely hearts columns to meet women. After police appealed for information following the murder of Leanne Tiernan in 2000, two women who had dated Taylor separately contacted authorities, citing disturbing behavior during their relationships with him. Both mentioned his familiarity with Lindley Woods, where Leanne’s body was later found, and revealed that he had openly boasted of poaching there.

Further investigation into his background uncovered a deeply disturbing sexual history. Several former partners disclosed that Taylor had a bondage fetish and expressed violent and sexually deviant fantasies, including tying women and their daughters with cable ties. One woman reported feeling as though she was being raped during encounters with him. Taylor's preferred method of restraint, using cable ties around the wrists and linking them behind the back, matched precisely the way Tiernan had been found. Police were soon able to build a strong profile of a man who, beneath a calm façade, harbored sadistic and dangerous tendencies.

On November 26, 2000, 16-year-old Leanne Tiernan was abducted while returning home from a Christmas shopping trip in Leeds. She was last seen walking down an unlit path known as Houghley Gill.

Taylor abducted Leanne, took her to his home, tied her up with cable ties, and strangled her. He kept her body in cold storage for several months before burying it in Lindley Woods, near Otley. Her body was discovered on August 20, 2001, wrapped in a floral duvet cover, green plastic bin liners, and tied with twine. A dog collar was found around her neck, and her hands were bound with cable ties.

Forensic evidence linked Taylor to the murder. A hair found on the scarf used to strangle Leanne matched Taylor's mitochondrial DNA. Twine used to bind the body was traced to a unique batch sold to the public, with a matching sample found at Taylor's home. Cable ties found on Leanne's body were identified as being manufactured by a company that supplied them to the Royal Mail, Taylor's employer.

Taylor was arrested on October 16, 2001. He initially claimed that Leanne's death was an accident, stating he had picked her up by the scarf around her neck. However, the evidence contradicted his claims.

On July 8, 2002, Taylor pleaded guilty to the kidnap and murder of Leanne Tiernan and received two life sentences. The trial judge stated that Taylor should expect to spend the rest of his life in prison.

Further investigations revealed Taylor's involvement in two separate rapes committed in 1988 and 1989. He pleaded guilty to these charges on February 4, 2003, and received additional life sentences.

In 2018, Taylor was sentenced to a whole-life order for a series of other rapes and sexual assaults, meaning he is now unlikely ever to be released.

Taylor is also suspected in several other unsolved murders, including the 1992 murder of Yvonne Fitt, a Bradford sex worker, whose body was found in Lindley Woods, the same location where Leanne Tiernan was buried.