911 Calls and DUI Stops

“FROM THE CLASSROOM”
By Ray Hill, Professor Emeritus, Santa Rosa Junior College

With the holiday season approaching, we typically see an increase in reports of suspected DUI's by 911 callers.  This important bulletin clarifies best practices by patrol and dispatch personnel on how to respond to such calls, including the decision to "follow and observe" or the duty to stop the vehicle immediately. 

Recently, I received an inquiry from one of the agencies I work with regarding a roll call discussion over “911” calls and DUI stops. The question was - If after receiving a dispatch, does there have to be some observation of a CVC violation or erratic driving before initiating an investigatory detention.

The case law answer is No!   Here are a U.S. Supreme Court case and California Supreme Court case on point:

After an anonymous "911" cell report of reckless driving, a CHP officer pulled over a Ford pickup truck on Hwy. 1 in Mendocino County. The caller had reported that the truck “had run her off the road”;  a full vehicle description was provided (including license plate number); and a mile marker and direction of vehicle travel (southbound on Hwy. 1) was provided by the reporting party. The vehicle was observed and followed for five minutes (while awaiting backup), but the officer viewed no illegal or unusual driving activity.  After the stop, officers detected the overwhelming smell of cannabis emanating from the truck bed. They searched and found four large bags containing 30 pounds of cannabis. U.S. ruled the call included an eyewitness report of the incident, location, and complete vehicle description A “false tipster” would think twice before using “911” because of the available technology to capture, record, and trace the call source information. Running another car off the road suggests impairment that is characteristic of DUI. The officer’s failure to observe any additional suspicious driving did not dispel reasonable suspicion to ....

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