Former Surrey Police constable Simon Quinn is jailed for 18 months after pleading guilty to misconduct in a public office.
The 43-year-old made £7,000 from tips to the tabloid over the course of a decade.
The court heard that Quinn had leaked information to a journalist about murder inquiries, including the Dowler case, from November 2000 until his resignation in January 2011. He had also passed on details of cases involving celebrities – both as victims and suspects.
Following his sentencing at the Old Bailey, the officer in charge of operation Elveden, Detective Chief Superintendent Gordon Briggs, said: “Quinn is the ninth police officer, and the 27th public official, to have been convicted for passing confidential information acquired in the course of their duties to journalists for financial gain.
“Trust and confidence in the police service is undermined when police officers behave in this way and the public interest is harmed. Their dishonest actions merit criminal convictions.
“It is the role of a police officer to serve and protect. Leaking sensitive and confidential information is an abuse of the trust the public hold in us.
“Victims of crime need to have complete confidence that they will get the support and help of the police and be treated with sensitivity and confidentiality.”
The case of Milly Dowler became the focus of public anger when it emerged that News of the World journalists had accessed voicemail messages left for the missing 13-year-old on her mobile phone, giving her parents false hope that she might still be alive and picking up her messages.
After admitting hacking Milly Dowler’s phone, The News of the World was closed by News International, and the incident prompted David Cameron to set up the Leveson inquiry into media ethics, to which Milly’s parents gave evidence.
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The Independent Police Complaints Commission (IPCC) later criticised Surrey Police for failing to act, despite officers at every level of the murder investigation knowing that an allegation of hacking had been made against the News of the World.
Former nightclub bouncer Levi Bellfield was convicted of Milly’s murder in 2011, nine years after she vanished while walking home from school in Walton-on-Thames in March 2002. He was given a whole life term for her abduction and murder.