A friend of mine was driving on the motorway, veered off and wrote off his car as was trying to retreive something that had fallen on the floor. He had no seatbelt on at the time. Will this invalidate his insurance as he told the Police officer on the scene?
It will not "invalidate" his insurance ie he will not be prosecuted for no insurance but the insurers will not doubt use the above factors to reduce the payout as they would with any other illegality. The Police may well pursue a "Due care" prosecution and also one for not wearing a seatbelt.