Allan Joseph Legere was born on February 13, 1948, in Chatham Head, New Brunswick, Canada. Legere worked as a mechanic and had a history of involvement in minor criminal activities before escalating to more violent offenses.

On June 21, 1986, Allan Legere, along with two accomplices, Todd Matchett and Scott Curtis, committed a robbery at a convenience store in Black River Bridge, New Brunswick. They cut the power and broke into the store, where they encountered an elderly couple, John and Mary Glendenning. During this crime, John was beaten to death, and Mary was assaulted. After the crime, Mary crawled to a phone to call for help, leading to the arrival of the police. The authorities quickly tracked down and arrested the three men. Matchett admitted to murdering John Glendenning, while Legere and Curtis were convicted after a trial.

On May 3, 1989, while serving his sentence in a maximum-security prison, Legere was taken to the Dr. Georges-L.-Dumont Regional Hospital for an ear infection. He tricked the guards into allowing him to use the washroom alone. In the washroom, Legere managed to pick the lock on his handcuffs using a sharp piece of metal he had hidden. He then escaped from the hospital and evaded capture through carjacking and stealing vehicles.

Legere remained free for about seven months. During this time, he committed four more murders in the Miramichi area. His victims included Annie Flam on May 29, 1989, and the Daughney sisters, Linda and Donna, on October 13, 1989. He set fire to the sisters' home before leaving. Father James Smith was murdered on November 16, 1989. Legere was captured on November 24, 1989, after a failed carjacking attempt that started in Saint John and ended near Rogersville. A reward of $50,000 led to his arrest.

Legere's trial for the murders began in November 1990. He was held in a jail in Fredericton during this period. In August 1990, he was sentenced to nine additional years for his escape. His murder trial was notable for being one of the first cases in Canada to use DNA profiling to convict someone. In November 1991, Legere was found guilty of the murders he committed while on the run.

By 2015, Legere had been moved from a super-maximum-security penitentiary to the Edmonton Institution in Alberta. The Fredericton jail he was held in during his trial was closed in 1996 and later turned into a science museum. In August 2020, Legere applied for day parole, which raised concerns in the local community. He had a parole hearing scheduled for January 13, 2021, where his request was denied.