Motor Vehicles: Testing Mr. Goodwill To ask the Minister of State, Department for Transport what recent assessment he has made of the effectiveness of the MOT test in identifying vehicles which may be dangerous due to blacking out or tinting of windows. Paul Clark The MOT test does not include a check of the level of light transmittance through tinted vehicle windows. To include this item in the MOT test would require all 19,000 MOT test stations to incur expenditure on special test equipment. This could involve a cost of around £10 million and there would be additional costs associated with calibrating and maintaining the equipment. Given that relatively few vehicles appear to have excessively tinted front windows we consider that the issue is best addressed through enforcement at the roadside.