” it is an offence, under regulation 30 of The Road Vehicles (Construction & Use) Regulations 1986 (SI 1986 No. 1078), to drive a vehicle in which the glass is maintained in such a condition that the vision of the driver is impaired.”
“The Road Traffic Act 1988 (as amended by Section 8 of the Road
Traffic Act 1991) Part II, 40A, Using Vehicle in Dangerous Condition, states that:
A person is guilty of an offence if he uses, or causes or permits another to use, a motor vehicle or trailer on the road when:
(a) the condition of the motor vehicle or trailer, or of its accessories or
equipment, or
…
is such that the use of the motor vehicle or trailer involves a danger of injury to any
person. “
http://www.legislation.gov.uk/uksi/1986/1078/part/II/chapter/E/made