A royal police officer who stole a dead woman's pictures to pose online as a 17-year-old girl "for kicks" has avoided jail.
Pc Adam Cox, 31, was working in Parliamentary and Diplomatic Protection when he created an alter ego called Emily Whitehouse to exchange explicit sexual chat with three men online.
On being asked to send them sexually revealing photographs, Cox found images online of a Canadian woman who committed suicide at the age of 21 and passed them off as "Emily".
Police investigating the Emily online chat raided his home last year.
They found 1,691 indecent and extreme images, with one featuring an infant and others showing children as young as seven.
He told police: "I'm not hoarding images. I have never meant to hurt anyone. I'm not a collector. I've not got a secret stash."
On his Emily persona, he said: "It's me. It's not me. It's madness, a way of escaping reality."
Cox, from Windsor in Berkshire, pleaded guilty at the Old Bailey to four counts of possession of indecent images - 645 of the most serious category A pictures, 201 category B, 449 category C, and 396 extreme pornographic images of bestiality.
He denied encouraging three men to attempt to get indecent images from "Emily" and the charges were ordered to lie on file.
Judge Mark Dennis QC sentenced Cox to 20 months in prison suspended for two years and 250 hours of unpaid work.
He said: "It should be a matter of enduring shame on his part that he engaged in this offending with complete disregard for his oath and responsibility as a serving police officer."
Prosecutor Charles Falk said Cox had been working for the Metropolitan Police with responsibility for the security of embassies, Parliament and the royal family.
Mitigating, Nick Yeo said Cox had expressed "intense remorse" and faced losing his job as a result of the case.
Judge Dennis said Cox had pretended to be a teenage girl "for kicks", adding it was "troubling" that he had yet to come to terms with what it was all about.
Harry Gibbs, 32, of Stevenage, Hertfordshire, Andrew Monk, 39, of Kettering, Northamptonshire, and Ajai Shridhar, 46, of Ealing, west London, admitted attempting to possess indecent images of children and were each handed a 12-month community order.
Cox has been made subject to a sexual harm prevention order and has been suspended from duty since his arrest.
The Met's Directorate of Professional Standards (DPS) will conduct a misconduct review once criminal proceedings are complete.