Warwickshire Chief Constable Andy Parker has said he was "embarrassed" that his officers had become involved in a heated anti-cuts campaign in the wake of the Plebgate incident.
"My officers got involved in a political campaign which was ill thought-through and has led to a lot of public confidence issues for us," he said.
"I would certainly like to apologise to Mr Mitchell because this added to the already big impact of the Plebgate campaign and it is embarrassing that my force was involved in the way it was."
The chief constable of West Mercia Police has apologised for the findings of an investigation that initially found three Police Federation officers who met Andrew Mitchell had no case to answer for misconduct.
Chief Constable David Shaw has overturned the earlier finding and written a personal letter of apology to the former Chief Whip.
He has asked for another chief constable to be called in to review the decision not to take action against the three officers.
He told the Home Affairs select committee: "Clearly the buck stops with me and I have to be accountable for a huge range of things that go on.
"It's unedifying and it hurts the force."
– Detective Sergeant Stuart Hinton from Warwickshire Police
We showed poor judgment in speaking to the media immediately following the meeting with Mr Mitchell. I think we are all happy to take the criticism on the chin for that.
What we should have done is given ourselves an opportunity to debrief the meeting.
We certainly didn't lie intentionally.
Chief Constable David Shaw of West Mercia Police has written to former Chief Whip Andrew Mitchell to offer "a profound unreserved apology" over the 'Plebgate' meeting.
He told MPs from the home affairs select committee, he wrote a letter on Monday which was "a personal apology from me".
"It was a profound unreserved apology for the impact what has happened has had on him", he added.
The chairwoman and deputy of the Independent Police Complaints Commission are appearing in front of MPs to answer questions over their report into the meeting between Police Federation officers who met former Chief Whip Andrew Mitchell after the 'plebgate' affair.
They questioned the "integrity" of the officers over giving a false account and have said the officers who met Mr Mitchell should have been facing charges of gross misconduct.
Referring to the findings of West Mercia police investigation into a meeting in the wake of the "Plebgate" scandal between three Police Federation officer and former Chief Whip Andrew Mitchell, Michael Ellis MP posed the question "are we dealing with a whitewash here?"
Deborah Glass, Deputy Chair of The Independent Police Complaints Commission, said: "There was certainly. I thought the conclusions were wrong".
The head of Professional Standards, Warwickshire and West Mercia Police has told MPs he thought three Police Federation officers had a case to answer in regards to their actions after meeting Andrew Mitchell after the 'plebgate' affair and didn't agree when "my superiors concluded otherwise".
Chief Inspector Jerry Reakes-Williams, He said that looking at a transcript of meeting and what the officers said there is not "clear case of lying...there is room for doubt".
Mr Reakes-Williams added: "I think the result was that the public were misled but I do not think it was a deliberate attempt to mislead."
Chief Inspector Jerry Reakes-Williams, who investigated whether Midlands police officers lied after a meeting with Sutton Coldfield MP Andrew Mitchell, has told MPs he disagreed with his senior colleagues.
– Chief Inspector Jerry Reakes-Williams, Professional Standards, Warwickshire and West Mercia Police
"I thought the three Police Federation men had a case to answer and didn't agree when my superiors concluded otherwise."
The Home Affairs Select Committee are hearing from Chief Constables, the IPCC and the Police Federation later today over 'plebgate', which led to Sutton Coldfield MP, Andrew Mitchell, resigning from his role as government chief whip.
Chief Inspector Jerry Reakes-Williams, who represents professional standards at Warwickshire and West Mercia Police is giving evidence.
He has said that comments made by officers after their meeting with Andrew Mitchell had the effect of misleading the public.
"I do not take the view that the view that they lied deliberately, hence why it was a case of gross misconduct, not misconduct."
CI Reakes-Williams has said that Mr Mitchell is owed an apology and also admitted that the row had damaged the reputation of the forces involved.
Andrew Mitchell has remained tight-lipped over whether he would hope to be vindicated over the 'plebgate' affair as he arrived at an airport in Washington.
MPs on the home affairs select committee are to question three Police Federation officers accused of misrepresenting the former Chief Whip after a meeting over the incident last year.