Chief Superintendent Dal Babu, 49, left the force Monday, The Guardian reported. He was in charge in Harrow, a north suburban borough of London.
Babu was denied admission in 2011 to the strategic command course for chief constables and decided to retire. The stated reason was that his media skills are inadequate, although he has been a prominent spokesman for Muslim officers.
"The police service is certainly a very different organization from the one I joined when racist name-calling was commonplace," Babu told The Guardian. "But my sadness is we have gone from 1 percent to 5 percent black and ethnic minority officers in 30 years. We have not managed to replicate the communities we serve. Our major cities are majority ethnic minority and yet the police force remains stubbornly white."
When he joined the police in 1983, Babu said there were times when he contemplated resignation because of the open racism. More recently, he sometimes faced problems because of his religion.
His file included a note that he was "racially over-sensitive," he said.
Babu has had successes, including organizing a program to provide one-on-one mentoring for black officers seeking promotion to chief inspector. But the Association of Chief Police Officers turned down his proposal for a broader program.
But Babu is glad he stuck with the police.
"Despite everything that has happened I have been incredibly lucky to be a Metropolitan police officer," he said.