I am a loss to understand why the police and the government do not take a tougher line on overtinted driver and passenger windows. These windows should have a light transmission of 70% but it is not part of the MOT test. Why not? It is absolutely vital to road safety to be able to make eye contact with other road users (especially for motorcyclists) but every day we see vehicles that are clearly in contravention of this rule. These vehicles should be impounded until made safe. I'm sure that the gauge for measuring light transmission through the glass cannot be that expensive (what price a life?), and if the MOT law was changed to embrace this standard then the price of the equipment would fall. The offending vehicles are very easy to spot, and so all police patrol cars should carry a gauge and issue a statutory fine. I have noticed that most of the offending vehicles are overblown 4x4s more intent on posing than road safety, but this practice is extremely dangerous and very easy for the police and government to solve. Thanks for an interesting and balanced column.