Conservative MP David Davis, the former shadow home secretary, said it is clear that former chief whip Andrew Mitchell has suffered an injustice an "all that remains is for him to go back into Cabinet."
Metropolitan Police officer Keith Wallis, who was today sentenced to 12 months in jail for lying about witnessing the infamous 'Plegate' incident involving Andrew Mitchell, wrote a drunken email to his MP falsely claiming that the former chief whip shouted "You ******* plebes" at officers.
Mr Mitchell said in a victim impact statement: "The existence of the emails contributed to my acute demoralisation and sense of isolation. They were therefore a contributory factor in the events which led to my resignation."
The Independent Police Complaints Commission (IPCC) has criticised "collusion" between officers involved in the 'plebgate' row.
Speaking after Pc Keith Wallis was jailed for 12 months for lying about witnessing the incident, the body's head Deborah Glass said: "The patchwork of evidence from emails, text messages and telephone calls does not suggest an organised conspiracy to bring down a Cabinet Minister.
"But there was clearly collusion between certain officers to, as they saw it, blow the whistle on bad behaviour toward one of their own, which ultimately had the same effect."
She added: "The actions of Pc Wallis - and the other officers responsible for turning a largely inaudible altercation lasting less than a minute into a national scandal - have not only caused injustice to Mr Mitchell, they have brought shame upon the police service.
"Now that the criminal proceedings have concluded it is important for the Metropolitan Police Service to proceed as quickly as possible to the misconduct hearings and to deal effectively with any underlying issues so that they can finally close the book on this sorry chapter."
A Metropolitan Police officer has been jailed for 12 months after pleading guilty to a charge of misconduct in public office over the "plebgate" scandal last month.
Pc Keith Wallis, 53, falsely claimed in an email that he had witnessed an incident in Downing Street involving the former Chief Whip Andrew Mitchell and other officers in September 2012.
Former Chief Whip Andrew Mitchell wrote an impact statement ahead of Pc Keith Wallis' sentencing for misconduct in public office over the "plebgate" scandal.
Britain's most senior police officer, speaking after the sentencing of Pc Keith Wallis, said that the officer - who is one year away from retirement - would now be the subject of a misconduct process "as soon as possible".
– Metropolitan Police Commissioner Sir Bernard Hogan-Howe
Pc Wallis's actions have clearly fallen way below the standards that me, my fellow police officers and the public demand.
I expect my officers to serve the public without fear or favour. Where officers break the law they must expect to be held to account and answer for what they have done.
Yesterday I apologised personally to Mr Mitchell that an MPS officer clearly lied about seeing him behaving in a certain manner.
Today, I apologise to the public for Pc Wallis's behaviour.
Two officers from the DPG have received final written warnings and a third officer has undergone management action in relation to inappropriate comments, the Met confirmed.
Wallis, along with four other officers from DPG, will be the subject of gross misconduct hearings due to start at the end of the month.
Labour MP Keith Vaz has said that a police officer's admission of misconduct over 'plebgate' is an acknowledgement of gross unfairness towards former chief whip Andrew Mitchell.
The Home Affairs Select Committee chairman said:
This plea is not only the first public acknowledgement that Mr Mitchell has been the subject of gross unfairness but it also an admission that a criminal offence has been committed against him.
With 11 other officers being subject to misconduct hearings, and the further investigation by the IPCC, this appears to be a complete vindication of Mr Mitchell's position.
– Home Affairs Select Committee chairman Keith Vaz
Lessons have to be learnt in order to restore full public confidence in way these matters are dealt with.
Now is the time to turn the page on this whole unfortunate incident which took only 45 seconds, but has cost the taxpayer hundreds of thousands of pounds, Mr Mitchell his job and damaged the reputation of the police.
Former Conservative chief whip Andrew Mitchell has welcomed the guilty plea of an officer charged with misconduct in public office over the 'plebgate' row.
In a statement, he said: "I am pleased that justice has been done in a criminal court today.
"It is very sad and worrying for all of us that a serving police officer should have behaved in this way. There remain many questions unanswered, in particular why Pc Wallis wrote this email and who else was involved in this process."
"I am looking forward to seeing justice done in the up to 10 other related disciplinary cases involving police officers so that I can focus all my energy on delivering for my constituents and help David Cameron win a Conservative majority at the 2015 Election."
A police officer who admitted misconduct in public office by falsely claiming to have witnessed the 'plebgate' row involving Tory MP Andrew Mitchell will be sentenced on February 6.
Pc Keith Wallis, 53, was charged after he sent an email to deputy chief whip John Randall, claiming that he had seen the incident involving other police officers in September 2012.
Mr Justice Sweeney released Wallis on unconditional bail but warned him that "all sentencing options remain open to the court".
The Sun's Political Editor Tom Newton Dunn, who broke the original 'plebgate' story, has claimed the police officer's admission today to falsifying witnessing the row, was merely "a red herring to the main event": the Downing Street PC who alleged Andrew Mitchell called him a "pleb".
Worth remembering Keith Wallis's part in #Plebgate came a day after the row at gates. So a red herring to main event; if Mitchell said pleb.
Also worth remembering PC Toby Rowland, who made 'pleb' allegation, has been fully vindicated by Met/CPS/IPCC, + he is still suing Mitchell.
A Sun spokesman said: "We stand by our story and will defend Mr Mitchell's claim vigorously".
Mr Mitchell is suing the paper for libel.
In a statement, he said: "I am pleased that justice has been done in a criminal court today....I am looking forward to seeing justice done in the up to 10 other related disciplinary cases involving police officers"