The senior journalist will take charge of one of the country’s largest media relations operations, with the Met running a 24/7 press bureau and numerous social media feeds.
The force has almost 50,000 followers on Instagram, 220,000 on Facebook, and 1.2 million on Twitter.
Greenwood joined the Daily Mail in 2011 and was the newspaper’s chief crime correspondent before being appointed executive news editor last December.
He previously worked for the Press Association, Sky News, and local newspaper York Press, and was the chairman of the Crime Reporters Association between July 2016 and January 2019.
Greenwood will be part of the senior leadership team in the Met’s directorate of media and communication, working with James Helm, director of comms; Ruth Shulver, deputy director of comms; Yvonne O'Hara, head of internal comms; and Stephanie Day, head of campaigns.
Helm said: "We are delighted to have Chris join us and add further strength and experience to the team, communicating with Londoners and working with the media to tell the story of the Met’s work every day."
Keen to get started
Greenwood commented: "I cannot wait to join the team communicating the extraordinary work and everyday heroism of the Metropolitan Police. The need for clear, timely and professional engagement between police and the media remains as pressing as ever."
He added: "I hope to build on a long history of success explaining the often difficult, complex and high-profile role of the world's greatest police force."
Ed Stearns and Anna de Vries are among those who have previously held the role of head of media at Britain’s biggest police force.
Greenwood has previously spoken of the "real hunger and determination for change" among "senior police communicators" in restoring relations between the police and media.
His comments were made in 2016, in the wake of the Leveson Inquiry prompted by the phone-hacking scandal at the News of the World.
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