SOUTH WINDSOR, Conn. (WTNH) — Determining if a driver is operating a vehicle while under the influence of cannabis takes specially trained officers — and more are stepping up to learn.

There are 62 drug recognition experts in the state, a number that continues to grow, according to Cpl. Kevin Geraci with the South Windsor Police Department.

“DREs aren’t new, they’ve actually been in the state for over 10 years,” Geraci said. “As a matter of fact, DREs did 170 enforcement evaluations last year.”

How Connecticut State Police plan to catch those driving while under the influence of marijuana

The Connecticut Department of Transportation is heavily involved. A state coordinator manages the program and is able to get grants to help with purchasing equipment.

A traffic stop involving a potential cannabis DUI case looks different. An officer will pay attention to a driver’s demeanor. That includes checking if they are confused, know where they are or are slow to answer questions.

If there is probable cause for an arrest, then the driver is brought to a police department for the drug recognition expert to examine.

The experts use a 12-step test to determine which of seven drug categories the driver is under the influence of. The test includes examining vital signs and having a driver perform tasks.