For the actions of the government the law is the definition of right/wrong, for better or worse (probably better, as otherwise right/wrong is strictly in the eye of the beholder, which is even more dangerous).

That's why so many people here defend companies like Google or Facebook for legally manipulating their accounting to pay less taxes.

Right/wrong is what the legislators are supposed to worry about when making the law, but once the law is set that's the framework.

So arguing about the legality does have a point here, as it indicates what parts of the law must be changed or erased completely to make our conceptions of right/wrong line up with what the law thinks.