The Highway Code states your windscreen "must be kept clean and free from obstructions" as failing to do so could cause a serious incident. Drivers who don't could face a £100 on-the-spot fine and three penalty points, which could rise to £1,000 if the fine is challenged in court. Motorists have been warned that one simple mistake before you even begin driving this autumn could see you face prison time. Neil said: "Anything that obstructs a driver's view, such as leaves and dirt, can lead to serious legal consequences. "If your driving falls below that standard, you could face charges of careless driving or dangerous driving depending on the degree of culpability.