Ex-director of public prosecutions Lord Macdonald said it is "outrageous" that the police force has yet to publish a conclusion about the 45-second incident outside Downing Street nearly a year ago which led to then chief whip Andrew Mitchell's resignation.
But the Metropolitan Police have said the inquiry is complicated and will "take as long as is necessary", while the Independent Police Complaints Commission (IPCC) has said "all that can be done to conclude the investigation is being done".
While the incident which sparked this investigation is on the face of it simple - it took less than a minute to unfold - what has evolved are allegations of a conspiracy which by its very nature is complex.
While I share the concerns of others that the investigation is taking far longer than originally anticipated, I am regularly updated on its progress, I am personally reviewing the evidence and I am satisfied that all that can be done to conclude the investigation is being done and that Mr Mitchell himself is kept informed.
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What separates us from the terrorists is that we air our grievances with non-violent debate though our democratic structures and processes.