Signs for 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 from 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 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 impair 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 the defense counsel for lack of cause.

Other indicators included on the NHTSA list include driving without headlights on, delayed reaction to traffic signs and 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.

DUI Checkpoints

There are several strategies used in checkpoints to filter out drunk drivers. The police may either stop every car or use a specific pattern to stop only specific cars. While the officers on the ground are conducting the actual searches, there are “chase” cars stationed in hiding spots at the checkpoint to drive after any cars that attempt to evade the checkpoint altogether.

During a stop, the officer will likely walk up to the car being stopped and begin speaking with the driver. He or she may ask questions about where they are driving from and whether they have been drinking. However, the conversation is just a cover for the actual investigation being conducted while the officer and driver talk. The officer is searching for signs from the behavior of the driver that may indicate that they have been drinking regardless of whether they admit to it. The signs searched for at sobriety checkpoints are more personal traits as opposed to actual motor skills.

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.

Free Consultation with an Attorney

Contact Rosenstein Law Group at 480-248-7666 to learn more about possible DUI defense strategies. We represent clients throughout Arizona from offices in Fountain Hills, Scottsdale, Mesa, Tempe, and Gilbert.


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