Our colleagues in America appear to have hit on a new way of keeping cars out of bus lanes.
I'm told that San Francisco's Muni bus system has recently equipped 30 of its buses with forward-facing cameras so they can take photos of vehicles illegally travelling along or parking in the city's bus lanes.
John Haley, transit director of the San Francisco Municipal Transportation Agency, reckons that the new cameras have transformed driver behaviour. “When cars see a bus coming, they get the hell out of the way now,” he says.
“Fifteen months from now, all of Muni's 819 buses will be equipped with the cameras. Drivers caught on tape violating the bus lanes will be subject to fines of up to $115. “
That's going to concentrate a few Californian minds.
Of course, forward-facing cameras are certainly not new on British inner-city buses, but I'm not sure anyone has thought of using them as a traffic enforcement tool. You could see how they could be useful in Central London, for example, though I doubt whether evidence derived from a camera mounted on the front of a bus would be admissible in a British Magistrate's court.
This might be a good thing, however. John Haley freely admits that with all these cameras at his disposal, he's starting to get a lot of experience with cameras.
“With all the footage, I'm starting to feel a bit like Cecil B. Demille," he gloats.
Ready for your close up, Mr Mayor?