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Anonymous Tips in DUI Investigations

In a decision announced in April of this year, the United States Supreme Court considered whether an anonymous tip of reckless driving, without any corroboration by law enforcement of the alleged reckless driving, could furnish reasonable suspicion of drunken driving thereby making an investigatory of the driver constitutionally permissible.  Under the facts of that case, the Court held that, under the totality of the circumstances, the officer had the requisite reasonable suspicion that the driver was intoxicated, and thus that the traffic stop was constitutional.

On August 23, 2008 in Humboldt County, California an anonymous tipster called 911 and reported that she had been run off the road.  The caller relayed the make and model of the car (a Ford F-150 pickup truck) as well as the vehicle’s license plate.  The caller also relayed on which roadway the vehicle was traveling and the direction in which it was traveling.  A California Highway Patrol officer traveling in the opposite direction passed the vehicle approximately thirteen minute after the 911 dispatch team aired the call, made a u-turn, and stopped the driver after following him for approximately five minutes.  During the time the police officer followed the vehicle the driver committed no traffic infractions.

Ultimately the police officer stopped the driver.  As the officer approached the vehicle he smelled marijuana.  The driver was not intoxicated.  However, a search of the truck bed revealed thirty pounds of marijuana.  The driver and his passenger were arrested and were later convicted of transporting marijuana, for which they sentenced to ninety days in jail plus three years of probation.  On appeal the California Courts held the stop constitutional, concluding that the officer had reasonable suspicion to conduct an investigative stop because the content of the tip indicated that it came from an eyewitness victim of reckless driving, and that the officer’s corroboration of the vehicle’s description, location, and direction established that the tip was reliable enough to justify a traffic stop.

In its majority opinion (authored by Justice Clarence Thomas), the Court began with an examination of the law concerning investigative stops.  The Fourth Amendment permits brief investigative stops, such as a traffic stop, when a law enforcement officer has “a particularized and objective basis for suspecting the particular person stopped of criminal activity.”  That principle applies to investigative stops based on information from anonymous tips.  The majority then considered the initial question in the case – “whether the 911 call was sufficiently reliable to credit the allegation that petitioners’ truck ran the [caller] off the roadway.”  In concluding that it did, the Court noted that the caller had reported that she had been run off the road by a specific vehicle, thus the caller necessarily claimed eyewitness knowledge of the alleged dangerous driving.  The Court also noted that the timeline of the events suggested that the caller reported the incident soon after she was run off the road.

The Court then turned to the question of whether the tip created reasonable suspicion that “criminal activity may be afoot,” i.e. whether the report of being run off the road created reasonable suspicion of an ongoing crime such as drunk driving.  The Court found that the driving behavior alleged by the 911 caller “viewed from the standpoint of an objectively reasonable police officer, amount[s] to reasonable suspicion” of drunk driving.  The Court reasoned as follows:

The 911 caller in this case reported more than a minor traffic infraction and more than a conclusory allegation of drunk or reckless driving. Instead, she alleged a specific and dangerous result of the driver’s conduct: running another car off the highway. That conduct bears too great a resemblance to paradigmatic manifestations of drunk driving to be dismissed as an isolated example of recklessness. Running another vehicle off the road suggests lane-positioning problems, decreased vigilance, impaired judgment, or some combination of those recognized drunk driving cues. See Visual Detection of DWI Motorists 4-5. And the experience of many officers suggests that a driver who almost strikes a vehicle or another object — the exact scenario that ordinarily causes “running [another vehicle] off the roadway” — is likely intoxicated.  As a result, we cannot say that the officer acted unreasonably under these circumstances in stopping a driver whose alleged conduct was a significant indicator of drunk driving.

Thus, although conceding it was a “close call,” the majority held that it was reasonable under the circumstances for the police officer to stop the driver.

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