Det.-Const. Timothy Kuttschrutter can tell if you are on drugs.

The York Regional Police drug recognition expert, one of two on the force and only 16 in the province, looks at those things a body can't control, such as blood pressure, body temperature and, of course, the constriction or dilation of the pupils.

"There are certain things in the body you don't have control over, no matter what you try," he said.

"Those are the telltale signs you may be impaired by a drug."

The average pupil is around three to 6.5 mm. Det.-Const. Kuttschrutter said he's seen the pupil of a person under the influence of a narcotic constrict to as small as 1.5 mm, the size of a pinhole.

The drug recognition expert program was started in 1979 by the Los Angeles Police Department.

Being certified as a drug detection specialist means an officer has the knowledge, skills and ability to form an expert opinion regarding impairment by drugs.

Right now, it's mainly being used to stop people from driving while under the influence of drugs, the officer said.

Once a driver is stopped, officers can perform a standardized field sobriety test, which may include things such as walking and turning or standing on one leg.

Since spring 2004, 25 front-line York officers have been trained to complete such tests, which help form reasonable grounds to suspect impairment by drugs or alcohol.

"What you look for with an impaired person is the inability to perform motor and mental skills," Det.-Const. Kuttschrutter said.

If the officer suspects the driver is impaired, an expert is called.

A 45-minute evaluation is performed by the expert, who will try to determine, through a series of psychological and physical tests, which category of drug the driver may have used.

Then they ask for a blood, urine or oral fluid swab sample to corroborate their findings.

As of the beginning of December, Det.-Const. Kuttschrutter and the force's other expert have performed nine consensual drug detection evaluations.

As a result, nine people have been charged with drug-related impaired driving charges. The cases have yet to make their way through the courts.

However, the real work is expected to begin should the federal government decriminalize marijuana.

Coming hand-in-hand with decriminalization is Bill C-16, introduced in the house of commons Nov. 1.

The bill proposes changes to the criminal code that would enable police officers to demand drivers suspected of being impaired by a drug undergo a standardized field sobriety test or a drug detection evaluation.

It would also make it an offence to refuse to provide an oral fluid, urine or blood sample on demand.

With relaxed public attitudes toward marijuana, the drug being increasingly used for medicinal purposes and decriminalization on the way, Det.-Const. Kuttschrutter, who will train other drug experts in the new year, expects to be busy.

"Right now, it's a learning curve for the guys on the road," he said. "This thing is really brand new for all of us."