but the point is that t's "ROAD" tax not "EMISSIONS RELATED" tax

road tax is supposed to pay for the upkeep of the roads and thats it

an emissions tax should be paid for by the original owner of the vehicle or at mot time

if your car wieghs more than another you should pay more road tax
if it weighs less you should pay less, the thinking behind this is that you wear away less of the road on a smaller lighter vehicles tyer than you would o a big lumbering juggernauts fat tyres

most of the policies made up are by people who don't actually inhabit this world of ours, they are up there with the super mario brothers or sonic in dipsy laa laa land dreaming up this cofusing new taxes while in some sort of power de ranged stupor