Here’s an overview of what cops typically look for in motorists’ behavior to serve as probable cause for DUI stops, our Adams County & Boulder DUI attorneys explain.

Here’s an overview of what cops typically look for in motorists’ behavior to serve as probable cause for DUI stops, our Adams County & Boulder DUI attorneys explain.

Before a law enforcement official can pull over a driver, there has to be probable cause for doing so. Probable cause refers to “reasonable grounds” for taking some action, and it is closely tied to people’s Fourth Amendment rights, which protects them from illegal search and seizure.

In terms of DUI stops, various things can serve as probable cause. However, transportation safety officials at the National Highway Traffic Safety Administration (NHTSA) have compiled a list of specific driving behaviors, assigning each with a percentage reflecting the probability that drivers who take each action are impaired.

This list (DOT HS-805-711) is used to train officers and guide them when in the field. Below, we will point out some of the more important aspects of this list to be aware of.

How Your Driving Behaviors Can Be Used to Predict Your Impairment

In determining whether a driver is likely to be intoxicated, based on his or her driving behaviors, here is what the NHTSA says are the top indicators of motorist impairment:

  • Turing with a wide radius – 65 percent (likelihood of intoxication)
  • Driving over the middle of lane markers – 65 percent
  • Nearly hitting an object or another vehicle – 60 percent
  • Not being able to drive straight/weaving – 60 percent
  • Swerving or driving on areas that are not designated roadways – 55 percent
  • Driving at least 10 mph under the speed limit – 50 percent
  • Stopping in a lane of traffic without any apparent cause – 50 percent
  • Drifting in and out of a lane of traffic – 50 percent.

Additional possible indicators of impairment that are associated with less than 45 percent probability of impairment but that can still serve as probable cause for DUI stops, according to the NHTSA include:

  • Erratic braking
  • Tailgating other motorists
  • Making illegal turns
  • Signaling in a manner that isn’t correlated with driving behaviors
  • Driving without headlights on at night.

Probable Cause for DUI Stops: Additional Important Information

  • Whatever the probable cause ends up being for your DUI stop, the traffic cop has to document it in his police report for the stop (if a citation or arrest results from the stop).
  • When there was no probable cause for making a DUI stop, any arrest or citation resulting from the stop can be invalidated or dismissed.
  • Even if there may be probable cause for DUI stops, what drivers do and say during these stops can provide police with the additional probable cause they may need to make a DUI arrest. So, the bottom line is that drivers should know their rights and be careful about what they say/do at every point during DUI stops.

Contact the Adams County & Boulder DUI Attorneys at Peter Loyd Weber & Associates

Have you or a loved one been charged with a DUI? If so, the Adams County & Boulder DUI attorneys at Peter Loyd Weber & Associates are ready to immediately start defending you. Our primary concern is protecting your constitutional rights throughout the criminal process while helping you obtain the best possible outcome to your DUI case.

To talk about your defense and how we can help you, call us today at (720) 863-7755 or email us using the contact form on this page.  We offer complimentary consultations, and we take pride in always being available to our clients – 24 hours per day, 7 days per week – so that they have the personal attention their case deserves.

From our offices based in Northglenn, Broomfield and Boulder, we provide the strongest defense and highest quality legal services to our clients throughout Weld County, Adams County and the state of Colorado.

Categories: DUI, DUI Stops & Arrests