A police officer who lied about witnessing the Plebgate row was jailed for 12 months today.
Keith Wallis, 53, of West Drayton, west London, sent an email to Conservative deputy chief whip John Randall, who was his MP, wrongly claiming that he had seen what happened as Andrew Mitchell left Downing Street on September 19, 2012.
Last month, the officer from the Metropolitan Police diplomatic protection group pleaded guilty at the Old Bailey to misconduct in a public office.
The court heard he admitted his lie in a police interview and offered to resign.
Mr Mitchell, then chief whip, became involved in a heated confrontation with another police officer, Toby Rowland, after he was refused permission to cycle through the main gate of Downing Street.
Following reports of the incident in 2012, the Sutton Coldfield MP apologised for being disrespectful to police but denied Pc Rowland's claim that he used the word ''pleb''.
But his apology was not enough to prevent members of the Police Federation of England and Wales protesting at the Conservative Party's annual conference in T-shirts bearing the slogan "Pc Pleb and Proud".
After meeting the MP in Sutton Coldfield, the federation's Inspector Ken MacKaill said he had "no option but to resign", while Labour leader Ed Miliband described him as "toast" in the House of Commons and Prime Minister David Cameron himself said his chief whip was wrong to use the words he did.
The unrelenting pressure eventually led Mr Mitchell to offer his resignation on October 19, a month after the initial altercation.
Following Wallis's guilty plea last month, Mr Mitchell said justice had been done and there were calls for his return to Government.
Met commissioner Sir Bernard Hogan-Howe apologised to Mr Mitchell and said that Wallis's behaviour fell "way below the standards expected" of his officers.
Mr Cameron also issued a statement saying it was "completely unacceptable" for police to falsify their account of an incident.
Mr Justice Sweeney said: "Passing sentence on you I am in no position to decide precisely what happened between the officers and Mr Mitchell in Downing Street nor do I need to do so, but it is absolutely clear what did not happen - you were not an independent member of the public, you were not present, neither was your nephew, and neither of you witnessed the incident.
"Yet, over a total period of nearly three months you pretended to your Member of Parliament and initially to the interviewing officers that all of those things were true including involving your nephew in the process."
Mr Sweeney went on: "This was thus sustained, and in significant measure, devious misconduct which fell far below the standards expected of a police officer. Indeed it was a betrayal of those standards, and was misconduct which as well as having had an impact Mr Mitchell himself, has had a significant impact on public trust and confidence in the integrity of police officers."
He added that police officers "must be deterred from misconduct and the public must be able to see that punishment will be visited upon police officers who betray the trust reposed in them".