"I went to a Hull police station the other day. They had five different police cars and they were just about to buy a £73,000 Lexus. There is money that could be saved to get the police on the frontline."
But he probably has not found £73,000 towards the budget deficit, as the car was brought and equipped a year ago
Hull police's response suggests that was misleading on several factual points.
The Telegraph reports:
Humberside Police have been operating the 175mph Lexus IS-F for over a year and are believed to have paid over £40,000 for it before it was fitted with £30,000’s worth of computer and communications equipment.
The chief constable defends its use as a frontline tool "as a mobile command centre in tackling cross-border crime in Yorkshire and the Humber".
The Metropolitan Police have also challenged Cameron's claim that "have 400 uniformed officers in their Human Resources Department when our police officers should be crime-fighters, not form-fillers" as misleading and out of context.
PoliceProfessional.com has their detailed breakdown, which suggests that over 300 of these police officers were engaged in training activities - 208 in "teaching new police officer recruits, specials and probationers" and others in training new PCSOs, driver training and other training roles.
Perhaps more will come out from the Conservatives about the rights and wrongs of the claims and counter-claims of these case over the next couple of days.
One would need to be a crime and policing specialist, which I am not, to comment on the resourcing decision - and Cameron is supposed to be a critic of national politicians wanting to micro-manage decisions, while naturally advocating value for money in public spending.
But it is a reminder that all of the party leaders will surely expect their specific claims, examples and anecdotes to be scrutinised and checked.
UPDATE: Cathy Newman for the Channel 4 News fact check scores this one as fiction - and reveals that the other day was in fact August 18th 2009.
And Cameron himself has a taxpayer-funded Lexus as leader of the opposition, having argued that the less expensive and greener Toyota Prius would be too small in 2006.