CAROL STREAM, Ill. (AP) – Police in northwestern Illinois will soon try out new tests meant to quickly detect if drivers have drugs in their systems.

Carol Stream police will begin testing drivers in February for marijuana, cocaine, amphetamines, methamphetamines and opiates like heroin.

The test is designed to be quick and portable. Officers will use mouth swabs. A mobile device will then test the swab and give officers measurements for amounts of drugs present.

Officers say they’re expanding their focus to drugs because they can often see the effects on drivers but can’t always identify the drug.

The system will begin testing on a voluntary basis because results can’t yet be used as conclusive evidence in court. Roadside tests would then be compared to blood tests police conduct afterward to see if they match.