In the two-and-a-half years that Sir Ian Blair has been Commissioner of the Metropolitan Police, no foe has proved a pricklier thorn in his side than the inexorable war protester Brian Haw.
During a midnight raid in May last year, Blair removed Haw from Parliament Square, where he had staged his one-man protest for the previous five years.
But in an embarrassing development, Blair is now set to appear at Westminster magistrates' court this afternoon to answer for the whereabouts of Haw's banners and placards taken during the raid.
"Yes, Sir Ian is on the list," confirms a court spokesman when I call. "It's in Court One this afternoon."
Among some of the items taken was a signed artwork by the graffiti artist Banksy, which is thought to be worth tens of thousands of pounds.
Understandably, Haw is keen to see it returned. Labour MP Alan Simpson recently asked after the fate of the painting, enquiring as to whether it would "turn up at an auction for the next policeman's ball".
It's the latest in a series of blunders over Haw that has proved embarrassing for Blair. After a district judge ruled in January that Haw's removal had been wrong, it was revealed earlier this month that the raid had cost £111,000 - considerably more than the £7,200 estimated by Blair last year.
On today's case, a Met spokesman said: "I don't think we'd comment on something like this."