According to Autocar in the UK, Scotland Yard has announced plans to replace half of its fleet of vehicles with either electric or air-powered vehicles within four years. We're not sure what air-powered vehicles are being considered, but we've been hearing about the compressed air vehicle from MDI for the last few years at least.
There are already 140 or so Toyota Prius hybrid police cars currently in use by the Metropolitan Police Service and officers have been putting electric versions of the smart fortwo through their paces. Those two programs are expected to continue and grow. Nigel Jakubowski, head of transport services, says, "The uniformed officers who have driven them say they are very quick. We have installed charging points at the stations the cars are based in, and they work very well."
This is a case of the right vehicle being used in the right situation. In a busy urban area like downtown London, for example, the limited top speed and range of electric vehicles isn't really a problem.