With medical marijuana set to be available in dispensaries statewide, and with the legalization of pakalolo gaining national momentum, when is it OK to get high and drive your car?

Specifically, when are you too stoned to safely operate a motor vehicle?

That is the question raised by House Concurrent Resolution 97, which passed a House Transportation Monday and now awaits a hearing in House Health.

The reso asks the state Department of Health to study the matter and determine a “reliable scientific threshold.”

The DOH opposes the idea, however, in part because the reso says nothing about providing staff and money to do the work.

In its testimony DOH also stated the following:

The National Institute on Drug Abuse has been studying this issue for many years and has been unable to establish a per se level for driving under the effect of marijuana. Blood cannabinoid analyses are challenging. Cannabinoid blood levels may persist even after several weeks of cessation thus complicating the interpretation of blood concentrations.

Although single blood concentration always associated with impairment for both occasional and frequent cannabis users would be ideal, there is no one blood concentration that will achieve this goal.

But Rep. Cindy Evans, the reso’s chief author, told the Hawaii Tribune-Herald, “I think that it’s really important that we do this now. Hopefully this is the beginning of the discussion.”