Hayman held the rank of Chief Constable of Norfolk Constabulary and Assistant Commissioner for Specialist Operations at London's Metropolitan Police, the highest-ranking officer responsible for counter-terrorism in the United Kingdom.
[1] In 1998, Hayman transferred to the Metropolitan Police and gained the rank of commander, taking charge of the force's drugs unit,[5] before moving on to head the Directorate of Professional Standards and to serve as an aide to the deputy commissioner.
[11][12] Hayman, along with Commissioner Sir Ian Blair, was criticised by the press and the Independent Police Complaints Commission over the mistaken shooting dead of Jean Charles de Menezes at Stockwell Underground station on 22 July 2005.
"[16] Hayman appeared before the Home Affairs Select Committee on 12 July 2011 when he confirmed that he had received hospitality from people he was investigating in relation to a criminal offence, although he regarded this as normal and operational matters were not discussed.
[17] During this hearing, Select Committee member Lorraine Fullbrook said that the public saw him as a "dodgy geezer" for the financial and sexual allegations surrounding his resignation from the police, for his "cosying up to the executives of News International" and for "the disaster" of his enquiry into the phone hacking scandal.