How Drunk Driving Charges Get Dismissed
In Arizona, along with every other state in the U.S., defendants are presumed innocent until proven guilty. This means that the burden of proof is on the state to supply the evidence needed to prove guilt beyond a reasonable doubt. What this means for a driving under the influence (DUI) charge is that the defendant or defense attorney can achieve a dismissal if they successfully call into question the evidence the prosecution has presented. Without this evidence, an individual cannot be convicted of a DUI charge.
Evidence in DUI Cases
What evidence is used in a DUI case? To determine this, take a step back and consider the events that led up to the drunk driving arrest and criminal charge.
The Nature of the Stop
- Traffic Violation – Police can stop you at any time for a traffic violation. You may have been pulled over for speeding, but ultimately arrested for DUI if the officer has reasonable suspicion to believe that you were under the influence.
- Reasonable Suspicion – Police may stop a driver if they observe behavior that gave them reasonable suspicion the driver was under the influence, such as swerving, drifting, or other types of erratic driving.
- Sobriety Checkpoint – DUI checkpoints are constitutional, but only some states utilize them. Arizona is one of those states. So long as police are following proper procedure, drivers can be arrested for drunk driving at one of these checkpoints.
Standardized Field Sobriety Tests (SFSTs)
- Walk-and-Turn – Officer will ask the driver to step out of the vehicle and take nine heel-to-toe steps, and then turn around and repeat those steps. If the driver cannot keep their balance, starts before the officer says “go,” takes the wrong number of steps, etc. this may be used as evidence to support a DUI arrest.
- Horizontal Gaze Nystagmus – Offer will check the driver’s eye tracking by using a pen or similar sized object. The driver is instructed to keep their head still and follow the object with their eyes only. If the driver’s tracking is not smooth or turns their head, this may be used as evidence to support a DUI arrest.
- One-Leg Stand – Officer will ask the driver to raise one leg six inches off the ground with their foot pointed out while they count aloud. If the participant sways, hops, loses balance, or puts their foot down, this may be used as evidence to support a DUI arrest.
- Other Tests – The three aforementioned SFSTs are the most commonly employed by law enforcement, but there are other tests such as breath tests, Romberg balance, finger-to-nose, pupil dilation, and more.
Breath, Blood, & Urine Tests
Drivers are not required by law to take the SFSTs, but failure to do so can result in an arrest. Once someone is arrested under suspicion of driving under the influence, they are typically taken in for a chemical test – usually breath or blood tests, but sometimes urine tests are used. If a chemical test reveals that a person’s blood alcohol content (BAC) is over the limit of .08%, they will likely be charged with DUI.
How DUI Evidence Is Challenged
Defendants and their DUI defense attorneys can aim to achieve a DUI dismissal by challenging any piece of the evidence mentioned above. Some examples include:
- If there was no reasonable suspicion to stop the driver, the evidence collected at the traffic stop must be dismissed.
- If the sobriety checkpoint was conducted unlawfully, the evidence collected at the checkpoint must be dismissed.
- If the officer failed to properly perform the SFST, then that evidence could be dismissed.
- If the officer failed to properly score the SFST, then that evidence could be dismissed.
- If the chemical test was not conducted within the proper time limit, that evidence could be dismissed.
- If the chemical testing facility failed to follow proper procedure or the testing equipment was found to be defective, then that evidence could be dismissed.
If any one of these crucial pieces of evidence is dismissed from the case, the DUI charge has little to stand on. Often, successful motions to dismiss certain pieces of evidence in DUI cases results in DUI dismissal.
How Many DUIs Are Dismissed?
More than one million drivers are arrested for drunk driving annually - 1,117,852 in 2014. Some data suggests that about 11% are charged but not convicted, and 72% of those arrested for DUI are not charged at all. With a competent DUI defense lawyer on your side, you may be able to get your DUI charge dismissed.