Mark Hobson killed four people in North Yorkshire over eleven days in July 2004. His girlfriend, Claire Sanderson, died on July 7. Her twin sister, Diane, died on July 17. The next day, July 18, a retired couple he had no known connection to, James and Joan Britton, died at their home in Strensall, a village outside York. Hobson was a 34-year-old former binman from Selby. In April 2005 he pleaded guilty at Leeds Crown Court to all four murders, and in May 2005 he was sentenced to life imprisonment.
Claire and Diane Sanderson were twin sisters, both 27. Claire was Hobson's girlfriend. Press Association reports at the time place the death of Claire on July 7, 2004, and that of her sister on July 17. Little about the sisters' lives was made public beyond that they were twins, 27 years old, and that Claire shared a home with Hobson.
Police first described the deaths of the twins to the public on Tuesday, July 20, 2004, two days after they came to light on the Sunday, July 18. AFP reported that police wanted to question Hobson, Claire Sanderson's boyfriend, about the deaths of all four people. At that stage detectives said they had not found a link between the sisters and the Brittons, although sightings and other evidence suggested the killings might be connected.
James Britton was 80 and his wife Joan was 82. They lived in Strensall, about 40 kilometers from Camblesforth, where the twins' deaths were reported. They were a retired couple. Their deaths came to light on the same Sunday as those of the Sanderson twins, July 18, 2004, and the prosecution later said they had died that day.
A daughter of the Brittons spoke at a police news conference in York and appealed to whoever was responsible for her parents' deaths to give themselves up.
Deputy Chief Constable Roger Baker of North Yorkshire Police said on July 20, "We want to speak to him about four murders." More than 100 staff were working on the inquiry. Police described Hobson as dangerous and warned the public not to approach him. AFP reported that he had a 2002 conviction for unlawfully wounding a man.
Press Association reported that police had been trying to trace him for a week when he was arrested on a Sunday afternoon in late July 2004 after a tip-off. Deputy Chief Constable Baker thanked the public for their help at a press conference at a York police station.
On July 30, 2004, Hobson, then 34, appeared at Harrogate Magistrates Court charged with four murders. The charges named Claire Sanderson, allegedly killed on July 7; Diane Sanderson, allegedly killed on July 17; and James and Joan Britton, allegedly killed in Strensall on July 18. He was remanded in custody, and on August 6, 2004, he appeared at Leeds Crown Court.
On April 18, 2005, Hobson, then 35, pleaded guilty at Leeds Crown Court to all four murders. Press Association said he was close to tears as he entered the pleas. The prosecutor, Paul Worsley QC, told the court that the killing of Diane Sanderson was premeditated. Notes in Hobson's handwriting, including a list of other names, suggested to the prosecution that he might have been planning more killings. The agency's account of the hearing gave the dates of the offenses as a range, July 10 to 19, 2004, which differs from the dates in the charges.
Hobson was sentenced at Leeds Crown Court on May 27, 2005, to life imprisonment for the four murders. The judge told him, "The damage you have done is incalculable," and added, "The enormity of what you have done is beyond words." No minimum term or whole life order was reported.
No appeal or review of the sentence was reported, and where he is held has not been made public.
The dates of the killings vary by report: the charges give July 7, 17 and 18, while one account of the plea hearing gives a range of July 10 to 19. The note about other names was described to the court as suggesting possible further killings; no further killing has been charged or attributed to him.
July 7, 2004: Claire Sanderson, 27, is killed (date as charged).
July 17, 2004: Diane Sanderson, 27, is killed (date as charged).
July 18, 2004: James Britton, 80, and Joan Britton, 82, are killed in Strensall; the deaths of all four people come to light the same day.
July 20, 2004: police name Hobson as the man they want to question about four murders.
Late July 2004: Hobson is arrested after a tip-off.
July 30, 2004: charged with four murders at Harrogate Magistrates Court.
August 6, 2004: appears at Leeds Crown Court.
April 18, 2005: pleads guilty to all four murders at Leeds Crown Court.
May 27, 2005: sentenced to life imprisonment.