What protection do trade plates give when test driving a vehicle?

What protection do trade plates convey when test driving a vehicle? My son and I test drove a car at an independent dealer. He put one trade plate on the front of the vehicle and did not accompany us on the drive. A subsequent check of the MoT revealed that it had expired in May 2017. I thought trade plates covered road tax and insurance, but does it cover a vehicle that hasn't been tested since May 2016?

Asked on 2 February 2019 by Iain Smith

Answered by Honest John
A trade licence only covers tax, nothing else. The trader's insurance should cover test drives but most insurers insist these are accompanied. With no MoT it is illegal to drive a vehicle on the road.
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