In our last post, we began speaking on the issue of what exactly it takes to be convicted of drunk-driving charges in Colorado. As we noted last time, it is not the case that prosecutors always need to have evidence that the defendant was at or above the legal limit for blood alcohol content at the time of arrest. Such evidence does make it easier to obtain a conviction, but it isn’t necessary in all cases.
All it takes for a conviction of DUI in Colorado is evidence of the influence of alcohol on a driver’s ability to safely operate their vehicle. For this purpose, prosecutors can make use of any suggestive evidence police may provide from their investigation. This includes evidence of moving violations like speeding or going too slow, swerving, aggressive driving, failure to use a turn signal, and similar offenses. These all go to the question of the driver’s ability to safety operate the vehicle, and police are on the lookout for such behaviors when patrolling for drunk drivers.
On the issue of the influence of alcohol, prosecutors may make use of officers’ observations of the person and demeanor of the suspect, including their speech patterns, the color of their eyes, their smell, not to mention the content of their verbal responses and
Field sobriety testing plays an important part to play in helping police officers build probable cause to make an arrest. Depending on how a driver performs on standard field sobriety tests in combination with observations of the suspect, officers may ask the driver to take a roadside breath test or simply go right to the arrest, after which the suspect will be asked to submit to an official breath test.
Field sobriety testing, to be sure, has some usefulness for discerning intoxication, but like other aspects of DUI investigation, not all forms of field sobriety testing provide an accurate measure of intoxication. In our next post, we’ll look a bit more at this issue and the evidentiary value of field sobriety testing.