Steven Norris has accused the Metropolitan Police of misrepresenting the capital's crime figures.
Mr Norris came second in the last mayoral contest
The Tory London mayoral candidate said he thought claims over falling crime figures showed police bosses were living in a "parallel universe".
He said in four years under Mayor Ken Livingstone, crime was up by 7% and violent crime increased by 20%.
Met Police chief Sir John Stevens has asked candidates not to exploit fear of crime during the election campaign.
Mr Norris told the BBC1's Politics Show the way crime figures were recorded was "inadequate" and misleading.
He said: "I live in this city with my own family and I know that the issue that people really care about is actually crime."
The former Tory transport minister said there had been a "very small drop" in overall crime in the past year.
But he added over the four years that Mayor Ken Livingstone had been in office it was up by 7% with violent crime increasing by 20%.
"That is what ordinary Londoners feel is their experience too," he added.
A spokeswoman for the Metropolitan Police said its crime figures were published online for the public to see.
"We don't get involved in political comments," she said.
Mr Norris also attacked Mr Livingstone's congestion charge which he described as "regressive".
Asked about his role as chairman of rail maintenance company Jarvis, which is involved in the part privatisation of the Tube, Mr Norris said he was seen as the "business candidate".
He added: "At the risk of being a gay icon, I am what I am, this is me."