If you went out and had a couple of drinks, you may think you’re okay to drive, but one false move could lead to you getting pulled over and investigated for a possible DUI. In Colorado, they employ the “expressed consent” law, which means you have the right to refuse a chemical test on the scene, but in doing so, you accept that you’ll be arrested and taken to the station to conduct the chemical test.

The ride to the station could give your body time to rid more of the alcohol or substance buildup in your system. Once at the station, law enforcement will instruct you to take a breath or blood test to measure your blood alcohol content (BAC). If you refuse, law enforcement can use your refusal as evidence against you in its case to charge you with a DUI. Additionally, your driver’s license will be suspended for one year, and you will have to blow into an ignition interlock device for one year when your license is reinstated, among other penalties. 

Your best defense would be to have the test administered in confidence that you’ll blow under the legal limit or to challenge the results as the test, especially breathalyzer tests, which are routinely inaccurate. The false readings are due to calibration issues, officer error, other elements on the person’s breath (dental medications (certain breath mints and mouthwash), or environmental elements (smoke and burnt plastic or adhesives).

Blood tests are substantially more accurate but are not without error. Human error and machine miscalibration can lead to an inaccurately high reading.

What else could lead to a false blood alcohol test?

Additional factors that can affect your BAC, which would not help you in court, but are good to be aware of, are your height, weight, muscle to fat ratio, and your gender or ethnicity (women and Asian or Native Americans have lower levels of the enzyme (dehydrogenase) in their stomach to break down alcohol). Thus, the alcohol will hold steady in their bloodstream longer and accelerate faster the more they drink.

Also, diabetic individuals who deal with ketoacidosis often deal with higher BAC levels.

Are you curious about the potential penalties for those convicted of DUI-related crimes? You have the right to know what you’re up against and what avenues of defense are available if you get charged.