Wikipedia
A bullbar or push bumper (also roo bar or nudge bar in Australia, moose bumper in Canada, and push bar, bull bar, or grill guard in the United States) is a device installed on the front of a vehicle to protect its front from collisions, whether an accidental collision with a large animal in rural roads, or an intentional collision with another vehicle in police usage. They range considerably in size and form, and are normally composed of welded steel or aluminium tubing, or, more recently, moulded polycarbonate and polyethylene materials. The "bull" in the name refers to cattle, which in rural areas sometimes roam onto rural roads and highways.
Studies have shown that using bull bars increases the risk of death and serious injury to pedestrians. This is because the bull bar is rigid, and so transmits all the force to the pedestrian, unlike a bumper which resists some force and crumples. Due to the number of deaths and injuries caused by the rigid fronts of cars, often with metal bullbars (in 2000 they caused 2,000 deaths 18,000 serious accidents per year in Europe), the sale of new metal bullbars which did not comply with the European Union Directive was banned. However, in the United Kingdom the sale and refitting of second-hand bars manufactured before 2007 or the use of pre-2007 bars already fitted is permitted as per the current MOT guidelines: "It is not illegal for vehicles to be fitted with bull bars, although the Department would not recommend their fitment unless it has been shown, through compliance with specified safety standards, that they do not pose an additional risk of injury to pedestrians or other vulnerable road users. There are no plans for legislation to require bull bars that are already fitted to be removed."