Virginia lawmakers mull roadside saliva tests to stop stoned drivers

Roadside saliva tests could be coming to Virginia as police look for ways to tell if people are driving under the influence of marijuana.

Why it matters: Unlike driving under the influence of alcohol, there's no breathalyzer-like tool police can use to quickly determine whether someone is high.

• Meanwhile, a recent survey by the state's Cannabis Control Commission found lax attitudes toward driving after using marijuana.

What's happening: Authorities are considering bringing so-called "oral fluid tests" to Virginia.

• The tests, in which an officer swabs the inside of a driver's cheek, are already in use in at least 24 states, according to the National Conference of State Legislatures.
• They aren't admissible in court and are only intended to help officers decide whether to pursue a more-invasive blood test.

What they're saying: "You swab the inside of someone's mouth, and you get a positive or negative, and it just gives you some indicators," Virginia Crime Commission executive director Kristen Howard told the Daily Press.

Yes, but: Lawmakers would have to approve the new tests, and some are skeptical.

• "There are all kinds of legal issues surrounding that, which I would want to have a discussion about and have answered before we authorize police officers to start sticking objects in people's mouths just because they're driving on the highway," state Sen. Scott Surovell, a Democrat from Fairfax, said at a recent Crime Commission meeting, per WRIC.

Of note: Even blood tests for THC are difficult to interpret.

• Alcohol is water soluble, which means it spreads evenly through the body, making it easy to test for impairment via blood or breath. But THC is fat soluble, meaning levels in the bloodstream don't necessarily correspond to what's happening in someone's brain, per NPR.
• So an occasional user could still be considered under the influence but have very little THC in their bloodstream, while a regular user could have a "moderate level of blood THC even when they're not high," NPR reports.

Despite that uncertainty, some lawmakers are also pushing to set a legal limit for THC in the bloodstream, which they say would make it easier to pursue DUI convictions — an approach favored by an association representing prosecutors.

What's next: The Crime Commission plans to vote on recommendations next month, which would then go to the General Assembly for approval.