What is a common signal of impairment that officers look for during a DUI stop?

Erratic or swerving lane changes are a key signal of impairment that officers are trained to identify during a DUI stop. When a driver shows difficulty maintaining a straight path or makes sudden or unpredictable lane changes, this behavior can suggest that the driver is not in full control of the vehicle. Factors contributing to impairment, such as alcohol or drugs, can affect coordination and judgment, leading to such erratic driving patterns.

In contrast, behaviors such as consistent speed, the appropriate use of turn signals, and following the speed limit generally indicate that a driver is operating the vehicle within normal parameters and is likely not impaired. Observing impaired driving behaviors, such as confusion in lane changing, provides officers with critical information to assess a driver's state and decide whether further investigation is warranted, including sobriety tests.