It is not just the cops who are looking for impaired drivers. The Washington State Patrol is asking for all motorists to be on the lookout for DUIs.

When you see a vehicle driving dangerously; call 911.

• The law allows use of a cell phone to report an emergency, and reporting an impaired driver is an emergency.

When you call 911, the operator is going to want to know:

• The location and direction of travel;

• A description of the erratic driving;

• A vehicle license plate number.

“We’ve found the average driver can do a pretty reliable job of spotting DUIs,” said WSP Chief John R. Batiste. “They do almost as well as trained troopers.”

During the first eight months of 2009, troopers contacted 47 violators reported via cell phone. Of those, 21 were arrested for DUI.

How do you spot an impaired driver? Watch for vehicles weaving along the road or crossing onto the shoulder or into the next lane and driving there for a while before jerking back into their original lane. Speeding up, slowing down and making abrupt lane changes without using their turn signals are all signs of impairment.

Keep in mind it is not just alcohol that causes impairment. In 2008, the patrol arrested over 20,000 drunk drivers. Of those, over 1,400 were impaired by drugs other than alcohol.