Sidney Harry Fox (1899 – 8 April 1930) was a British petty swindler and convicted murderer. He was executed for the murder of his mother in an attempt to obtain money from an insurance policy on her life. His case is unusual in that it is a rare example of a known matricide in the United Kingdom. His murder was detected by then recent advances in forensic pathology. However, in 2021, an episode of Murder, Mystery and My Family suggested that his conviction was 'unsafe', stating it likely that his mother died of heart failure and the fire was indeed accidental.