The police investigation in to the "Plebgate" affair which led to the resignation of former chief whip Andrew Mitchell has cost nearly £150,000, it emerged.
Codenamed Operation Alice, the Scotland Yard inquiry was launched after claims that officers may have lied about the dispute with Mr Mitchell when they refused to let him leave Downing Street on his bike via the main gate in September last year.
In a letter from Deputy Assistant Commissioner Patricia Gallan, leading the investigation, to Keith Vaz, chairman of the Commons Home Affairs Select Committee, it was disclosed the cost of the police investigation had reached £144,000.
DAC Gallan wrote: "It remains that I have 30 officers at my disposal and the Operation Alice is estimated to have cost £144,000 to date."
"Four people have been arrested and no individual is currently charged. The advice file submitted to the CPS by the MPS (Metropolitan Police Service) has specifically asked for advice and guidance surrounding the future of the investigation in relation to potential criminal charges."