The Metropolitan Police will be fighting crime in pint-sized Smart Electric Drive (ED) city cars from next month, as part of a new trial. Four police-liveried versions of the tiny zero-emissions two-seater will be deployed on routine police patrols in central London and Heathrow airport.The aim of the trial is to gather data about the Smart ED's performance in everyday life. It's powered by a 41bhp electric motor, is capable of 60mph and has a range of 70 miles. Coppers will then have to recharge the Smart ED's batteries from a standard three-pin powerpoint plug.This isn't the first time the police have used a Smart car on patrol.The City of London used the first generation of the city car as an emergency response vehicle in 2002. Local councils also controversially use Smart cars fitted with CCTV cameras to monitor central London streets. Dermot Kelly, managing director, Mercedes-Benz Cars, said, "This Smart ED market trial is an important part of our commitment to sustainable mobility".