Yesterday the Vermont House Committee on Transportation considered H. 237, a bill to implement roadside saliva testing for THC and lowering the permissible BAC limit from .08 to .05 for any person with “any detectable amount” of THC in his or her blood.

Let’s talk about the commonsense reasons saliva testing is a bad idea.

Possession and adult use of marijuana will soon be legal in Vermont, and medical marijuana already is. This law punishes people for having even the smallest possible detectable amount of a legal substance in their body. We know that THC can remain in saliva for up to eight days after a person’s last exposure to cannabis, meaning that THC could very well be present long after the driver was able to operate a vehicle safely.

Even Governor Scott’s Marijuana Advisory Commission has said that, as study after study has shown, there is no scientifically reliable standard level of THC in the body that we can associate with driver impairment. If we can’t determine an amount of THC that would cause impairment, what exactly are we testing for?

Now, let’s talk about civil liberties.

This bill would justify the arrest a motorist in Vermont for having any detectable amount of a legal substance in his or her body. This immediately raises serious due process concerns.

Saliva testing without a warrant is an infringement on personal privacy. It is more invasive than a breathalyzer test because our saliva carries our DNA. And while the bill does not allow for the ‘extraction’ of DNA, taking someone’s saliva includes taking their DNA, and the Vermont Supreme Court has ruled that Vermonters have a greater expectation of privacy when their DNA is involved.

Finally, data collected by state law enforcement agencies shows massive racial disparities in traffic stops and searches, with Black and Latino motorists bearing the brunt of searches, even though searches of white drivers are more likely to yield contraband. We have every reason to believe that those disparities would persist in stops and searches related to marijuana impairment.

And at last, some good news.

We already have a test for driver impairment: the standard field sobriety test that has been used for decades to test for impaired driving, including individuals suspected of being under the influence of marijuana. Field sobriety tests focus on actual impairment rather than an unreliable indicator like THC in saliva.

Road safety is important, but THC saliva testing does nothing to make Vermont’s roadways safer while raising a host of civil liberties concerns, so, we’ll ask one more time: Why are we talking about it again?