We've not had a good fake police story for a while. Here's one, though; Californian driving a car kitted out as a police vehicle stops a real policeman and gets arrested. It's not quite as good a story as all that - the real police car was an unmarked one, so the symmetry isn't perfect. Apparently they think he planned to rob the guy; surely you wouldn't plan to be the only fake policeman on the streets?
Or perhaps he was working on the principle that being robbed by cops was a plausible event in Oakland, which is telling if true.
Much, much more seriously, the Guardian concludes that the kidnapping of Peter Moore in Baghdad in 2007 was a police-as-fake-police job, perhaps Iraq's distinctive contribution to violence. It's argued that they wanted rid of him to prevent the implementation of a huge management-information system that would track all payments to government contractors, and therefore bring about an epic reckoning of just how much money was being stolen.
If true, it's well worth pointing out that he wasn't the only foreigner to pay the price for resisting the spectacular corruption festival we created in Iraq; the fate of Dale Stoessel, for example, remains a mystery. He was involved with a contract to dispose of surplus military equipment, at the same time as the famous 99 tonnes of arms imported from Bosnia in the Ilyushin-76 ER-IBV failed to arrive in the Iraqi arsenal. The aircraft frequently went on elsewhere from Baghdad; I've long suspected that the weapons were being re-exported, or possibly sold to the insurgents.
Interestingly, we do have at least one case of valuable goods being simply driven out of the front door of Baghdad Airport. Special detail: the perpetrator was a fake private contractor.