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Colorado Criminal Defense and Personal Injury Attorneys

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Boulder Criminal Defense and Personal Injury Attorneys



Boulder DUI Attorney

DUI laws in Colorado are strictly enforced. And despite public efforts to encourage ride alternatives and campaigns to raise awareness, good people sometimes make a mistake. If you have been arrested for DUI, you need a skilled criminal defense attorney to protect your rights.

In Colorado a DUI charge means that the State believes it can prove that you drove a motor vehicle — or virtually any vehicle, including a golf cart, bicycle, skateboard, boat, or even a horse – when you have consumed alcohol or drugs such that you are affected to a degree that you are substantially incapable of exercising clear judgment, sufficient physical control, or due care in the safe operation of a vehicle.

DUI is a misdemeanor criminal offense in Colorado unless you have three or more prior alcohol/drug driving convictions, including convictions for vehicular assault or vehicular homicide, in which case a fourth DUI offense will be charged as a Class 4 felony.

The fact that you are legally entitled to use a particular drug under Colorado law (for instance medical or recreational Marijuana, a prescription medication, or even an over-the-counter remedy) does not provide you with a defense to a charge of DUI. The law means any drug or combination of drugs — to include inhaled glue, aerosol, or other toxic vapor(s), alone, together, or in combination with alcohol.

The proof in most DUI cases includes the results of a blood chemical test or a breath chemical test to determine blood alcohol content (“BAC”), or the presence of drugs or intoxicants. However, you can be prosecuted and convicted of a DUI offense even if you refused to take a chemical test.

The attorneys at Mertes Law are former DUI prosecutors who have since successfully defended clients charged with DUI offenses throughout Boulder County, Colorado, including the cities of Boulder, Longmont, Erie, Louisville, Lafayette, and Superior in addition to the Front Range of Colorado.

What is “DUI per se”?

DUI “per se” is a simpler way for prosecutors to charge and prove a DUI criminal charge. Rather than requiring that the State prove beyond a reasonable doubt to a judge or jury that you were operating a vehicle while affected to a degree that you are substantially incapable of exercising clear judgment, sufficient physical control, or due care in the safe operation of a vehicle, the DUI per se law relies upon the results of a blood or breath test to establish that you tested with a blood alcohol level (BAC) above .08 BAC within two hours after driving. It is not unusual to see a police officer charge someone with both DUI and DUI per se.

It is a defense to a charge of DUI per se that you consumed some alcohol between the time you stopped driving and the time of the test of your BAC. This means that if properly raised as a defense, a prosecutor must prove beyond a reasonable doubt that the minimum .08 blood or breath tested BAC was reached as a result of alcohol you consumed before you stopped driving.

Your DUI lawyer is entitled by law to offer direct or circumstantial evidence to show any disparity between what chemical tests of your breath or blood BAC show and other facts which could infer that testing was defective or inaccurate. This includes offering the testimony of non-expert witnesses relating to the absence of any or all of the common symptoms and signs of intoxication for the purpose of attacking the accuracy of the analysis of your blood or breath tested BAC.

What is a DWAI?

In Colorado being charged with Driving While Ability Impaired (“DWAI”) means that the State believes that it can prove that you drove a motor vehicle — or virtually any vehicle, when you have consumed alcohol or one or more drugs or a combination of alcohol and one or more drugs, such that you are affected to the slightest degree either mentally or physically — or both mentally and physically — of exercising clear judgment, sufficient physical control, or due care in the safe operation of a vehicle. DWAI is a misdemeanor criminal offense in Colorado.

DWAI is also considered to be a “lesser offense” to the crime of DUI in Colorado. This means that a judge or jury deliberating over the question of whether you were Driving Under the Influence will necessarily be asked to consider whether you were Driving While Impaired if they do not find that you were DUI.

What is a “Baby” DUI?

Under Colorado law it is a Class A traffic infraction for a person who is under the age of 21 to drive a vehicle when his or her BAC is above .02, but below .05 BAC at the time of driving or within two hours after driving. This offense is titled Underaged Drinking and Driving (UDD) but is commonly referred to as a “Baby DUI.” A judge has the discretion to punish a Baby DUI with up to 24 hours of community service and to impose an alcohol assessment and treatment for a first offense.

Express Consent

In Colorado any person who drives any motor vehicle upon the streets and highways and elsewhere throughout this state shall be deemed to have expressed their consent to take and complete any test or tests of the person’s breath or blood for the purpose of determining the alcoholic content of the person’s blood or breath when so requested and directed by a law enforcement officer having probable cause to believe that you were driving a motor vehicle in violation of Colorado law concerning DUI, DUI per se, DWAI, and UDD. This is known as Colorado’s Express Consent Law.

While you may elect between a breath or a blood test, you are not permitted to change your test selection. Persons under the age of 21 who are under investigation for UDD are subject only to breath alcohol testing. A law enforcement officer who is facing extraordinary circumstances may independently elect to change the type of chemical test you are administered. Extraordinary circumstances justifying a change of your chemical test election include, but are not limited to weather-related delays, high call volume impacting medical personnel, power outages, and malfunctioning breath test equipment.

Express Consent testing must occur within two hours of your last established driving in order to trigger a license revocation order under Colorado’s Express Consent Law. However, a BAC test taken beyond two hours may still be used by the State as evidence at your criminal trial.

Failure to provide a chemical test when requested by a law enforcement officer under Colorado’s Express Consent Law can subject you to the loss of your license and driving privilege.

Colorado’s Express Consent Law only applies to you when you are operating a motor vehicle. DUI investigations involving non-motorized vehicles do not trigger the law.

Upon refusing a chemical test, or having a test result with a BAC above .08, your driver’s license will be seized and you will be issued a temporary driving permit which expires in seven days. You have seven days to request a hearing with the Colorado Department of Motor Vehicles (DMV) on any Express Consent Notification you are given by law enforcement after a refusal or breath test result of .08 or higher, or an Express Consent Notification which comes to you later in the mail on cases involving BAC analysis by blood testing.

It is critical that you consult with your Mertes Law DUI lawyers in order to preserve your right to an Express Consent hearing and to help you make the choices involved in requesting a hearing, which include: Do you want the DUI officer to appear? And, are there any other witnesses that should be called to support your defense?

What Role Do Chemical Tests Play?

In Colorado a jury hearing a DUI case will be instructed by the Court about the inference they may draw from the results of your BAC test.

In any prosecution for the crime of DUI a driver whose BAC is shown to be .08 BAC or above gives rise to the permissible inference that he or she was under the influence of alcohol.

In any prosecution for the crime of DWAI a driver whose BAC is shown to be .05 BAC, but less than .08 BAC, gives rise to the permissible inference that he or she was impaired by the influence of alcohol.

If in any prosecution for the crime of DUI-Drugs (Marijuana) if a driver’s blood test results show five nanograms or more of delta 9-tetrahydrocannabinol (THC) per milliliter in whole blood, such fact give rise to a permissible inference that he or she was under the influence of one or more drugs.

Regardless of any legal inferences that can be drawn from the results of chemical testing your Boulder DUI attorneys at Mertes Law can introduce evidence bearing upon the question of whether you were under the influence or impaired when operating a vehicle such as the testing of second blood samples and careful toxicological analysis can provide important evidence to rebut any inference the State makes against you.

Please know that in any case where you’ve refused a law enforcement request to take, complete, or cooperate with the completion of a test the fact of your refusal can be presented to the jury as evidence at your trial, as can any effort on your part to reconsider your refusal.

Do Roadside Sobriety Tests Matter?

There are three standardized tests approved for use by the National Highway Traffic Safety Administration (NHTSA) which are used by officers investigating Colorado DUI cases. Collectively, these tests are known as Field Sobriety or Roadside Sobriety Tests. The NHSTA-approved battery of Roadsides include the Horizontal Gaze Nystagmus test, the Walking and Turning test and the One Leg Stand.

Some medical conditions can invalidate roadsides as measures of intoxication or impairment. These include optometric problems, such as amblyopia or lazy eye, convergence/divergence disorder, binocular disorders, and wearing hard contact lenses.

Do you have a history of orthopedic injuries that may affect your ability to perform balancing tests? Have you had past closed-head injuries, concussions, or loss of consciousness from trauma (which could include high school sports, skiing, snowboarding, and workplace or motor vehicle accidents)? Any of these conditions can create false “clues” on Roadside Sobriety Tests that officers are trained to interpret as signs of impairment or intoxication during a DUI investigation. Medical records reviews and consultation with a toxicologist and other professionals may lead to possible defenses related to established medical conditions, such as:

  • Gastric reflux disease, or “GERD.”
  • Diabetes, hypo-glycaemia or other blood sugar disorders.
  • Dental issues, including dental caps, tooth cracks, gum issues, and the presence of cavities or depressions which can contribute to mouth alcohol issues and impact the validity of BAC testing by breath.
  • Any medical conditions and/or drug interactions that may give rise to a defense of involuntary intoxication.
  • Any cerebellar (e.g. brain stem) disease or degeneration, such as pseudo tumor.

Roadside Sobriety Tests may also include the administration of a portable DUI breath test.

Roadside sobriety testing conducted as a part of a DUI investigation constitutes a full “search” in the constitutional sense of that term and therefore must be supported by probable cause. The Colorado Supreme Court has found that the sole purpose of roadside sobriety testing is to facilitate police efforts to acquire evidence of criminal conduct against you. Your Boulder DUI lawyers understand that intrusions into your privacy for the exclusive purpose of gathering evidence of criminal activity against you have traditionally required, at the outset of the intrusion, probable cause to believe that a crime has been committed.

What this means is that a roadside sobriety test can only be administered when there is probable cause to arrest the driver for an offense such as Vehicular Assault, Vehicular Homicide, DUI, or DWAI offenses which involve intoxicating liquor or other chemical substances, or when the driver voluntarily consents to perform the test. Unlike the requirements of Colorado’s Express Consent Law, you never have to consent to Roadside Sobriety Testing.

Colorado Courts have determined that to be voluntary your consent to a Roadside Sobriety Test must be intelligently and freely given, without any duress, coercion or subtle promises or threats calculated to flaw the free and unconstrained nature of the decision. It is important to note that you do not have to prove that you consented – this is the prosecutor’s job. If your consent to take a Roadside Sobriety Test was not voluntary your Boulder DUI Attorney can move to have this evidence suppressed and excluded in your trial.

A careful and thorough analysis of your case and possible defenses can make all the difference in defending against a life altering conviction for a DUI offense. Don’t let a DUI arrest ruin your life, call the experienced Boulder DUI lawyers at Mertes Law now for a free consultation and advice.

Mertes Law Firm | Boulder DUI defense lawyerCall 303-440-0123 to begin building your DUI defense.

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