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How Do Police Officers Search For Drunk Drivers?

Posted on June 27, 2019 in assault & violent crimes

There are several ways that police officers are able to spot drunk drivers. Regardless of whether the stop is made on the road or through a DUI checkpoint, there are several characteristics that have been shown to indicate impaired driving. This type of behavior is what police officers and highway patrolmen look for when searching for drunk drivers. While these driving choices are not always because the driver is impaired, it does offer the officer enough reason to be suspicious and therefore make a traffic stop.

Police officers may also increase their searching tactics for DUI on holidays or special occasions that may increase the amount of drunk drivers on the road. Under such circumstances, the police force will likely conduct road-blocking checkpoints to individually screen cars for impaired drivers. These DUI checkpoints are strategically placed in locations where there is likely to be more drinking than other places. The checkpoints are based less on a driver’s behavior on the road and more on a face-to-face experience between the officer and the driver. While the signs officers look for in checkpoints are different from those on the road, there are several key traits that may lead them to conduct a field sobriety test or breath test of the driver.

Signs of DUI on the Road

When police officers are patrolling the streets, it is their job to pursue driving behavior that seems suspicious. The list used by most police forces is based off of research conducted by the National Highway Traffic Safety Administration on telling signs of impaired driving.

Turning: Police officers are searching for cars that take turns at an unusually wide radius or turns that are too sharp. Additionally, abrupt or illegal turns can be a signal of a driver who is not using sober judgment. Such turning maneuvers do not necessarily have to be illegal in order to warrant a stop by a police officer or highway patrolman.

Driving lanes: Because drunk driving is primarily a danger to other drivers on the road, the most telling behavior for an impaired driver is how they make judgments concerning the cars around them and the lanes they drive in. Police officers are looking for cars that weave across lanes and make unsafe lane changes; straddling the center lane marker, or driving while partially in two lanes or with the tires on the center lane marker is also considered suspicious behavior. Furthermore, drifting between lanes, driving too close to other cars and questionable use of turning signals are also signs that police officers look for when searching for drunk drivers.

Speed: Unusually slow speeds, at least 10 mph under the speed limit, can be a sign of impairment and the subject of many traffic stops for DUI. Police look for rapid acceleration and deceleration without any apparent reason. Strangely enough, high-speed driving was not included among the list of indications compiled by the National Highway Traffic Safety Administration. This is because speeding requires quick judgment calls and fast reflexes, the very traits that intoxication subdues. Because of this, DUI stops made because of high-speed driving are often contested by Phoenix DUI attorneys for lack of cause.

Other indicators included on the NHTSA list include driving without headlights on, delayed reaction to traffic signs, excessive braking. More obvious behavior may include hitting or almost hitting another car, driving in the opposite direction of traffic or drifting out of a designated highway and driving off the road altogether.

Signs of Inebriation

While the officer is speaking with the driver of the car, he or she is looking for symptoms of intoxication such as watery or bloodshot eyes, a flushed face and clumsy motor skills. Obvious signs of drinking would include an admission or the smell of alcohol in the car or on the driver’s breath. At some point, the officer may even ask the driver to step out of the vehicle. At this time, the officer is watching to see if the driver sways or stumbles while stepping out of the car, leaning on the car for support or seems unable to follow instructions.

The conversation can also tell much about the driver’s state of mind. Overly flippant behavior can show the officer that the driver is unable to grasp the seriousness of the situation. Furthermore, combative or argumentative responses to the officer’s questions are enough to warrant further investigation into the impairment of the driver. DUI arrests are often a result of the lack of comprehension or awareness during the checkpoint procedures and while this behavior is not enough to arrest the driver at that very moment, it is reason enough to conduct field sobriety tests or breathalyzer tests that may serve to incriminate the driver. Contact a Phoenix criminal defense lawyer today at (480) 456-6400 if you or a loved one is facing DUI charges.

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