Paper or Plastic?

Seattle is proposing the first-in-the-nation attack on bags at grocery stores: a $0.20 fee for using paper OR plastic rather than bringing your own bag to the store.

I'm normally quite a skeptic of government trying to mandate well-intentioned outcomes, and question whether government (rather than the market) should be the arbiter of the best way to determine things like this. But I also believe that sometimes it is only the government can make a negative externality explicit, and I think that this sort of policy is the right way to achieve it. The fee is optional (you don't have to pay it if you just bring your own bag), and they're providing bags for the poor to avoid the unintended consequence of taxing the people who can least afford it.

Governments should not mandate free-choice behavior like this. But setting up incentives that make doing the "right" thing a natural choice? Bring it on!