A scientist has been jailed after 245,000 child abuse images were found in his computer in a police search of his home after he sent Theresa May a satirical poster of the then-prime minister decapitated.
Dr Christopher Doyle, 54, sparked a counter-terrorism investigation when he sent an envelope marked "C/O: The Nazi Party" along with an angry pro-Russia rant and a mysterious white powder – thought to be fake poison.
The former Cambridge University researcher’s letter was intercepted before it reached the Tory leader and the substance found to be harmless citric acid.
Doyle, who once worked at the government’s top secret laboratory Porton Down, denied sending a substance intending a person to believe it was noxious, claiming he was being “set up” by MI5.
He was found to have 245,505 child abuse images on his computer when his home was searched.
Doyle, of Widnes, Cheshire, previously admitted downloading the files - of children as young as six - but suggested to jurors many of them were legal and "artistic".
Police charged Doyle with one count of hoaxes involving noxious substances or things; one count of making indecent photographs of children; and one count of possession of indecent photographs of children.
He was found guilty on Thursday and was sentenced over both the fake poison and images at Liverpool Crown Court.
Judge Anil Murray said: "This was a serious offence intended by you to induce fear of danger to human life.”
During the trial, Joe Allman, prosecuting, said Doyle's letter to the PM was diverted to a screening facility in London on 5 April last year by a "greatly concerned" worker.
Specialist police said the envelope was stamped 28 March at Warrington Mail Centre and a mixed DNA profile on the stamp pointed to Doyle.
It included a poster of Theresa May decapitated, from satirical French magazine Charlie Hebdo.
Within a second envelope inside was a cartoon of Alexander Litvinenko, who died after he was poisoned in London in 2006, and a volatile message criticising the PM's policy towards alleged Russian involvement in the poisoning of both Mr Litvinenko and Sergei Skripal, who survived being poisoned in Salisbury in 2018.
Doyle said he believed MI5, MI6 or the government had opened his letter, were angered by what he had written, and must have planted the citric acid.
He said he was ashamed of his Category C indecent images, which included 188,540 videos.
Pritchard said a report showed Doyle had "genuine remorse" for the indecent images, but was still coming to terms with his offending.
He said: "The defendant suffers from bipolar affective disorder and has essentially been living with agoraphobia, barely leaving the house, since 2013 following the death of a close friend.
"He is a man who has gone from being a successful research fellow at Cambridge University to living in almost isolation.
Judge Murray said the scientist sent the fake poison at a time when "the issue of poisoning was high in the nation's consciousness".
Doyle eventually accepted the images were indecent at trial.
Judge Murray said the letter was "sophisticated enough to cause the fear you wanted to cause" and Doyle was a "highly intelligent man" who had not acted in the "spur of the moment" and had "full insight" into what he was doing.
Jailing Doyle for 34 months - two years and 10 months - and also ordered him to sign on the sex offenders register and to comply with a sexual harm prevention order for seven years.