 The matter was brought to the attention of the police, who were unable to find sufficient evidence to bring charges; the Shipman Inquiry later blamed the police for assigning inexperienced officers to the case.Between 17 April 1998, when the police abandoned the investigation, and Shipman's eventual arrest, he killed three more people.Several months later, Hyde taxi driver John Shaw contacted the police, informing them that he suspected Shipman of murdering twenty-one of his patients.