I know that Mothers Against Drunk Driving has endorsed the idea of what are called per se limits for cannabis. I think MADD has supported the idea of a five-nanogram limit for an oral swab test. We've had testimony about per se limits that would suggest there are problems with that. I wonder if you could speak a little more about that.
Then afterwards I'll ask Dr. Mayers if anything from the perspective of scientists about this would shed some light, although I realize your expertise is in the alcohol field.
Mr. Murie.