Are shaded car windows legal?

ChrisNW If glass is not tinted but driver is wearing sunglasses, is this the same legally? It has the same effect what they see on the road.

Not a problem on bright days, but some idiots wear shades even when it's dark cos they think they look hard, eh?

What about those lenses that change their shading depending on how bright it is? They could be a serious hazard to everyone, not only cyclists when travelling through patches of light/shade.

that's the thing, eyeshades, you can take them off. but i dont see any reason for that idiot to roll down his tinted window on a freezing/rainy/snowy night.