Educated at Marlborough College and King’s College, he joined the Met in 1981 and led investigations into more than 20 murders.
The senior Metropolitan Police officer was made assistant commissioner in December 2006 with a wide portfolio covering police complaints, intelligence, legal matters and high-profile inquiries.
The field of counter-terrorism was added in 2009 when he took over from Bob Quick, who resigned after revealing a secret document on terrorism to photographers.
Yates’s job meant he was seldom out of the media spotlight. In 2001, as a detective superintendent, he led an inquiry into internal police corruption centred on a crime squad based in East Dulwich.
It resulted in the jailing of six serving detectives.
He hit the headlines over his involvement in the “cash-for-peerages” investigation, after which he failed to persuade the Crown Prosecution Service to press charges under the 1925 Honours Act.
He was at the centre of the row over the shooting of Jean Charles de Menezes and handled the failed prosecution of royal butler Paul Burrell.
His hard work was recognised when he was formally moved up from his role as deputy assistant commissioner to become the Met’s fifth assistant commissioner — the third highest post in Britain’s largest police force.
And for a long time he was seen as a strong future contender for the top job after a career spanning three decades at the Met.
But his decision in July 2009 not to launch an investigation into claims that hundreds of people had their phones hacked by the News of the World ultimately came back to haunt him.
Despite all the recent allegations, he defended that decision last week when questioned by MPs.
Now the investigator has become the subject of an inquiry himself, choosing to resign after being told he would be suspended as his conduct was being referred to the Independent Police Complaints Commission.