MATTAWA - If you are a marijuana user and think that the legalization of pot in Washington State has given you free reign, you may want to think again.

According to Mattawa Police Chief John Turley, marijuana can still get you into trouble. You have to be careful how much you possess and what you do with it, especially in your car.

"You would work it like a DUI," Turley said.

The first thing you need to know is that the legalization of marijuana makes it legal only for people 21 and older. An adult found giving or selling marijuana to a minor would face "contributing" charges, Turley said. The minor would be charged with illegal possession.

Possession is legal up to 40 grams, Turley said. If an adult has more than 40 grams, he or she can be charged with illegal possession.

According to Turley, police do not go out looking for marijuana. They deal with it if found during another type of investigation.

"We are not going to break into a marijuana party unless we are called to the location for some other reason," he said. "Even then, if the people are using but possession is within the limits of the law, there is no problem."

In the case of a traffic stop, if marijuana is found in the vehicle but is not used, that is okay as long, as the amount is within the law. However, if the officer can see that the driver appears to be using or he can smell smoked marijuana in the car, the stop becomes a DUI matter.

"We would do a field sobriety test, like we do for alcohol," Turley said. "They're not entitled to use it while they are driving."

If needed, Turley said, the officer would get a warrant to draw blood from the driver so that it could be tested at the Washington State Patrol lab. If the result came back positive days later, the driver would be arrested and charged.

Neither are walkers entitled to use marijuana while in public, Turley said. Those cases are treated as public intoxication.

"You can't drink in public," he said. "You can't smoke marijuana in public."

In regards to the medical marijuana law, the pot must be prescribed and the user must carry his or her card at all times, Turley said. The card that allows use does not mean free reign either. Public intoxication and driving laws still apply.

"And there are only certain registered providers where they can get the marijuana legally," Turley said.

According to Turley, a medical marijuana user may possess 15 mature plants and 15 ounces of usable marijuana at one time. A medical user who is registered as a supplier for one other medical user may possess double the figures.

"A medical user who is a provider for another medical user must be registered, and he or she cannot provide for more than one other user," Turley said.