A Single Breathalyzer For Both Weed And Booze

One gadget could help cops catch lots of intoxicated drivers

Still from Cheech and Chong, Up In Smoke
Breathalyzer or not, this is probably not the best idea.Screenshot, Sanket Mahapatra via YouTube

Whether it's for medicinal or recreational purposes, marijuana has recently become more (legally) available in dozens of states all over the country. Where there are substances, there are drivers illegally operating vehicles under the influence. DUIs for driving while high might soon become much more common; a company called Hound Labs has developed a breathalyzer test for THC, the active ingredient in marijuana, that can also test for blood alcohol concentration, Reuters reports.

Pot-smoking drivers can be charged with a DUI, no matter whether or not recreational marijuana is legal in their state. But it's more difficult for officers to catch smokers than drinkers—THC exists in the bloodstream at much smaller concentrations than alcohol, so you need a different type of breathalyzer technology to detect it. Plus, marijuana affects the body differently, so field sobriety tests are totally ineffective. For now, police use blood or urine tests to prove that a driver had THC in his system, but those can take days, and can't assess how recently a person used marijuana.

Hound Labs says it has developed a new way to detect THC from just one or two breaths. There aren't many details about the science behind the device—the company's web site notes that the "science is proprietary, [so] we cannot go into too much detail about how it works," only claiming that the new method will be fast and accurate. And while there is another THC breathalyzer in development, this one could also read a driver's blood alcohol concentration, which is more cost-effective and useful for police than carrying two separate devices. It's a silver bullet against cross-faders.

Experts agree that marijuana impairs drivers, though not as much as alcohol does. But what concentration of THC makes a driver legally impaired? That's a question still very much open for debate, especially in states like Oregon and Colorado where recreational marijuana use is legal. The legal limits that these states currently have in place are both arbitrary and "useless," Hound Labs CEO Mike Lynn told Reuters. More research could answer this and many more questions about how marijuana affects the body, but governmental and regulatory systems are still standing in the way.

Assuming that its clinical trials go well, the THC/alcohol breathalyzer is expected to be available in late 2016, and will likely cost about $1,000, the same price as most of the breathalyzers in use now.