More on Banning Plastic Bags

In the comments, Chris Wold, a law prof at Lewis and Clark law school in Oregon who specializes in trade and environment issues, adds some details about the proposed ban on plastic bags in Oregon:

the bill may look discriminatory to a panel: no plastic bags are made in Oregon but plenty of paper bags are.

He adds:  "That is likely to complicate any discrimination analysis under Art. III and Art. XX."

That definitely complicates things.  There's a clear benefit to the Oregon paper bag industry from the measure.  I would think a panel would take that into account, either implicitly or explicitly.  But would that be the end of the story?  Could a panel get past this and find no violation, or find that the measure is justified?  What could they use to reach that conclusion?  Chris mentions the following:

The motivation for the bill is clearly environmental: environmentalists have been trying to get such a bill passed in Oregon for years now because plastic bags clog recycling machines and frequently wind up in rivers, oceans, etc.

Would this be enough?