Along with Washington, a second state has qualified pot legalization for the November ballot:

The Colorado measure, if approved by voters, would legalize possession of up to an ounce of marijuana or up to six plants for cultivation, said Mason Tvert, co-founder of the Campaign to Regulate Marijuana Like Alcohol. It would also set up a regulatory framework for the sale of cannabis products and the application of sales and excise taxes, in addition to legalizing the cultivation of industrial hemp.

And how will Colorado handle stoned drivers? In Washington recently, medical marijuana activists have been opposing I-502 by misrepresenting scientific studies to claim that its DUI provision will nab sober drivers and innocent pot patients. There's no provision like that in the Colorado initiative. So what will Colorado do? A state senate committee there has now advanced a bill that says "drivers would be considered impaired if they test positive for 5 nanograms or more of THC, the psychoactive ingredient in marijuana, per milliliter of blood," the Denver Channel reports. (Read the full bill here.)

That's the same limit in the Washington initiative.

In short, when initiative fails to address DUI for pot, the legislature won't let it slide (for obvious reasons) and will attempt to replicate the exact same automatic cutoff as Washington's initiative. Let's be realistic: If pot activists don't include DUI regulations, legislatures will likely do it for us—either before an initiative passes or afterward. As I pointed out last week, that THC cut off is one backed up by the evidence for giving drivers an increased risk of crashing. Back to the Denver Channel story:

"Five nanograms is more than fair," Cindy Burbach, forensic toxicologist for the Colorado Department of Public Health and Environment told senators.

Not only are I-502's critics misreading the science, they're misreading the politics.