A company vehicle driver cannot be held responsible for no insurance if he had no reason to believe it wasn't insured;
i.e company not in financial trouble, fleet of many vehicles, car or van was taxed.
It would probably apply the same to MOT, unless the driver had sole use of the vehicle and arranged it's servicing.
Tax is different as the driver can clearly see if it is taxed.

Road Traffic act 1988;
(3) A person charged with using a motor vehicle in contravention of this section shall not be convicted if he proves—
(a) that the vehicle did not belong to him and was not in his possession under a contract of hiring or of loan,
(b) that he was using the vehicle in the course of his employment, and
(c) that he neither knew nor had reason to believe that there was not in force in relation to the vehicle such a policy of insurance or security as is mentioned in subsection (1) above.



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