BERKELEY, CA (WCMH) — Police have alcohol breathalyzers to combat drunk driving, and they may soon have marijuana breathalyzers available to them.

“We had to develop some new chemistry that can actually be done. It was not obvious when we started that we could tag this,” Chemist Matt Francis, with the University of California-Berkeley told KTXL.

Francis has spent the last year trying to find ways to find pot on a person’s breath.

Some police however say it’s pretty obvious when a person is stoned.

“I think for most of our officers, impaired is impaired. They can see that based on their training and experience,” said Sgt. Davis Dowty with the California Highway Patrol.

However, Dowty does say a marijuana breathalyzer could make it easier to get a conviction after an arrest.

“Because they don’t have a tool, like with alcohol, it’s very difficult for them to say ‘okay. All these things that you saw, that’s wonderful and you may have been right, officer. But we need to convince a jury,'” Davis told KTXL.

Mike Lynn with Hound Labs said his company has been working on a pot breathalyzer for a long time. Hound Labs breath test device would be able to detect both alcohol and marijuana.

“We have tremendous interest from not only law enforcement, employers, who are struggling with this problem, but also the cannabis industry who knows you can’t be driving stoned. Everybody really accepts that,” said Lynn.

Lynn also argues that a breathalyzer would be the best defense for pot users who are pulled over, but not stoned.

Hound Labs breathalyzer costs less than $1,000 and is expected to be available starting next year.