For a driver age 21 or older in an ordinary car, what BAC level meets Colorado’s DUI-per-se threshold at the time of driving?
Correct answer: 0.08 or more.
The DUI-per-se threshold is 0.08. The law also addresses testing within two hours after driving. A result below 0.08 is not permission to drive while impaired.
Source: Colorado Revised Statutes 2026, section 42-4-1301 (2)(a); current on September 13, 2026. ↗
An adult driver says, “My BAC is 0.07, so Colorado cannot treat my driving as alcohol-impaired.” Is that correct?
Correct answer: No. Being below 0.08 does not rule out impaired driving.
A BAC above 0.05 but below 0.08 permits an inference of impaired ability and may be considered with other evidence. It is not the 0.08 DUI-per-se threshold.
Source: Colorado Revised Statutes 2026, section 42-4-1301 (6)(a)(II) and (6)(b); current on September 13, 2026. ↗
Alcohol makes a driver slightly less able than usual to use clear judgment and control the car, without making the driver substantially incapable. Which Colorado impairment definition fits?
Correct answer: Driving while ability impaired, or DWAI.
DWAI includes alcohol or drugs affecting ability to the slightest degree so the driver is less able than usual to exercise judgment, control or due care. A driver need not appear completely incapacitated.
Source: Colorado Revised Statutes 2026, section 42-4-1301 (1)(b) and (1)(g); current on September 13, 2026. ↗
A drug has made a driver substantially incapable of exercising clear judgment or sufficient physical control. Which rule applies even without alcohol?
Correct answer: Colorado’s prohibition on driving under the influence.
DUI covers alcohol, drugs or a combination when their effects substantially prevent safe judgment, physical control or due care. Alcohol is not a required ingredient in a drug-DUI violation.
Source: Colorado Revised Statutes 2026, section 42-4-1301 (1)(a) and (1)(f); current on September 13, 2026. ↗
A 20-year-old drives with a breath-alcohol result of 0.03 at the time of driving. Does being below 0.08 avoid Colorado’s underage drinking-and-driving rule?
Correct answer: No. The under-21 rule includes BAC from 0.02 through 0.05.
Colorado’s UDD provision applies to a driver under 21 with a breath-alcohol result at least 0.02 and not more than 0.05. Other impaired-driving offenses depend on their own requirements.
Source: Colorado Revised Statutes 2026, section 42-4-1301 (2)(d)(I); current on September 13, 2026. ↗
A driver is legally authorized to use medical marijuana. Does that authorization excuse driving while it impairs the driver?
Correct answer: No. Legal authorization to use a drug is not a defense to impaired driving.
The law specifically says entitlement to use a drug, including medical marijuana, is not a defense to DUI or DWAI. Permission to use a substance does not mean permission to drive while affected.
Source: Colorado Revised Statutes 2026, section 42-4-1301 (1)(e); current on September 13, 2026. ↗
A driver’s ability is impaired by a combination of alcohol and a drug, rather than by either one alone. Does Colorado’s impaired-driving law cover the combination?
Correct answer: Yes. It expressly covers alcohol combined with one or more drugs.
DUI and DWAI both cover alcohol, drugs and combinations of them. The relevant issue is their effect on safe driving under the applicable definition.
Source: Colorado Revised Statutes 2026, section 42-4-1301 (1)(a), (1)(b), (1)(f) and (1)(g); current on September 13, 2026. ↗
A blood test shows five nanograms or more of delta-9 THC per milliliter of whole blood. What does Colorado law say this result permits?
Correct answer: An inference that the driver was under the influence of drugs.
The statute calls this a permissible inference, not an automatic conviction or a safe-driving cutoff. The DUI definition and other competent evidence still matter.
Source: Colorado Revised Statutes 2026, section 42-4-1301 (6)(a)(IV) and (1)(f); current on September 13, 2026. ↗
What action brings a motor-vehicle driver within Colorado’s expressed-consent testing law?
Correct answer: Driving a motor vehicle in Colorado.
A person who drives a motor vehicle on Colorado streets, highways or elsewhere in the state is deemed to have expressed consent to this law. Specific testing requests must still meet the law’s conditions.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (1); current on September 13, 2026. ↗
An officer has probable cause to believe an adult driver committed an alcohol-related driving offense and lawfully directs a formal blood or breath test. What is required?
Correct answer: Take and complete the required test and cooperate with it.
For the qualifying alcohol-related offenses, expressed consent requires taking, completing and cooperating with the formal test. This is different from a voluntary preliminary roadside screen.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (2)(a)(I); current on September 13, 2026. ↗
For a formal alcohol test, a 30-year-old driver requests a blood test. No medical or extraordinary circumstance changes the normal choice. Which sample should be tested?
Correct answer: The driver’s blood.
Under the normal alcohol-testing provision, a driver 21 or older who requests blood receives a blood test. Special medical or extraordinary circumstances can affect the procedure.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (2)(a)(I) and (2)(a.5); current on September 13, 2026. ↗
A driver age 25 lawfully chooses not to have blood drawn for a formal alcohol test and can complete a breath test. No special exception applies. Which test follows?
Correct answer: A breath test.
For an adult’s normal alcohol-test election, requesting no blood draw leads to a breath sample. It does not cancel the obligation to complete testing.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (2)(a)(I); current on September 13, 2026. ↗
After choosing a formal alcohol test, a driver wants to switch simply because of a change of mind. No medical or extraordinary circumstance applies. Is that an unrestricted choice?
Correct answer: No. The chosen test normally must be completed.
Once blood or breath is elected, the driver generally cannot change the election. The statute provides specific exceptions, including qualifying extraordinary circumstances, rather than an unrestricted right to switch.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (2)(a)(II) and (2)(a.5); current on September 13, 2026. ↗
A driver cannot physically complete a breath test because of an injury. What does Colorado’s expressed-consent provision specify?
Correct answer: Use a blood test for the alcohol sample.
When injury, illness or another listed physical condition prevents taking or completing the breath test, the statute provides for a blood test. Genuine physical inability is not treated as a mere preference to change tests.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (2)(a)(II); current on September 13, 2026. ↗
A power outage beyond the officer’s control prevents the elected breath test within the required period. The officer explains this and directs a blood test. What must the driver do?
Correct answer: Cooperate with and complete the alternative test.
Qualifying extraordinary circumstances can require the other test. Complying with the officer’s required change is not itself a refusal; failing to complete that alternative can be.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (2)(a.5)(I)-(IV); current on September 13, 2026. ↗
After a qualifying formal alcohol-test request, how must a driver cooperate with the sample-collection timing?
Correct answer: Allow the sample to be obtained within two hours of driving.
The cooperation duty is intended to allow blood or breath collection within two hours of driving. It is not permission to delay until the end of that period.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (2)(a)(III); current on September 13, 2026. ↗
A driver agrees to a required formal test but refuses the collection consent form required by the authorized clinic. What does the cooperation rule say?
Correct answer: Required collection forms are part of cooperation; refusal can count as refusing testing.
The statute includes signing release or consent forms required by authorized specimen collectors. Noncooperation with those collection requirements is treated as a refusal.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (3); current on September 13, 2026. ↗
A driver deliberately stops cooperating before completing the chosen formal test, with no medical or statutory exception. Does starting the test satisfy the duty?
Correct answer: No. Failure to complete and cooperate is treated as a refusal.
Expressed consent requires completion and cooperation, not just selecting or starting a test. The scenario excludes medical inability and other exceptions that may change the procedure.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (2)(a)(II); current on September 13, 2026. ↗
A driver has already given a sample for a preliminary roadside breath screen. Does that screen replace a later lawfully required formal expressed-consent test?
Correct answer: No. The preliminary screen does not substitute for the formal test.
Colorado expressly distinguishes the preliminary screening test from the tests required by expressed consent. A qualifying formal request can still require completion afterward.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (7); current on September 13, 2026. ↗
During a lawful contact, an officer describes a preliminary breath screening test and advises that the driver may agree or refuse. How is this different from a qualifying formal test request?
Correct answer: That preliminary screen is voluntary; the formal testing duty is separate.
The preliminary-screen provision requires an advisement that the driver may agree or refuse. Do not confuse that screening procedure with the separate expressed-consent test requirements.
Source: Colorado Revised Statutes 2026, section 42-4-1301 (6)(i)(I); 42-4-1301.1 (7); current on September 13, 2026. ↗
An officer has probable cause of drug-impaired driving and reasonably requires formal drug testing under expressed consent. Is an alcohol breath sample the only kind the law can require?
Correct answer: No. The drug-testing provision includes blood, saliva and urine tests.
The drug-testing provision covers blood, saliva and urine when the legal conditions are met. The driver must cooperate so the required sample can be obtained within two hours of driving.
Source: Colorado Revised Statutes 2026, section 42-4-1301.1 (2)(b)(I)-(II); current on September 13, 2026. ↗
A driver refuses to cooperate with a required formal chemical test and later stands trial for DUI or DWAI. Must the refusal be kept out of the trial evidence?
Correct answer: No. The formal-test refusal may be admitted as evidence.
The statute makes refusal of the required formal testing admissible in a later DUI or DWAI trial. This is not the same rule as the voluntary preliminary screen, and admissibility is not an automatic conviction.
Source: Colorado Revised Statutes 2026, section 42-4-1301 (6)(d); current on September 13, 2026. ↗
An adult rear-seat passenger in an ordinary private car holds an open can containing beer while the car travels on a public highway. The driver is sober. Is the passenger’s possession allowed just because the passenger is not driving?
Correct answer: No. The passenger-area rule also applies to that passenger.
In an ordinary private car, a person in the passenger area may not knowingly possess an open alcohol container on a public highway or its right-of-way. Driver sobriety does not create a passenger exemption.
Source: Colorado Revised Statutes 2026, section 42-4-1305 (1)(d) and (2)(a); current on September 13, 2026. ↗
A partly used wine bottle still contains wine and has been recapped. Does replacing the cap make it a sealed, unopened container under Colorado’s rule?
Correct answer: No. A broken seal or partly removed contents still meets the definition.
The definition includes a container holding alcohol that is open, has a broken seal, or has had some contents removed. Recapping a partly used bottle does not undo those facts.
Source: Colorado Revised Statutes 2026, section 42-4-1305 (1)(c); current on September 13, 2026. ↗
In an ordinary car on a public highway, does putting an open alcohol container in the glove compartment place it outside the defined passenger area?
Correct answer: No. The law specifically includes the glove compartment.
The passenger area includes spaces readily accessible from a seating position and specifically includes the glove compartment. Hiding a container there does not make it outside the rule.
Source: Colorado Revised Statutes 2026, section 42-4-1305 (1)(d); current on September 13, 2026. ↗
A person in an ordinary private car parked on a public highway’s right-of-way starts drinking beer. Does being stopped rather than moving remove the state’s passenger-area restriction?
Correct answer: No. The rule also applies on the highway’s right-of-way.
The statute covers a motor vehicle on a public highway or its right-of-way, not only a vehicle currently moving. The scenario is not one of the listed passenger or storage exceptions.
Source: Colorado Revised Statutes 2026, section 42-4-1305 (2)(a); current on September 13, 2026. ↗
Under Colorado’s statewide alcohol-container rule, which location is a listed possession exception in a vehicle that has no trunk?
Correct answer: The area behind the last upright seat.
For a vehicle without a trunk, the statute lists the area behind the last upright seat as a possession exception. This does not authorize drinking, impaired driving or violating stricter local rules.
Source: Colorado Revised Statutes 2026, section 42-4-1305 (2)(b)(III) and (3); current on September 13, 2026. ↗
A front-seat passenger in a vehicle used primarily to transport people for compensation claims the paid-transport alcohol exception. Does that exception include the front passenger?
Correct answer: No. It excludes both the driver and the front-seat passenger.
The specific paid-transport passenger exception excludes the driver and front-seat passenger. It is not a vehicle-wide permission to possess or drink alcohol.
Source: Colorado Revised Statutes 2026, section 42-4-1305 (2)(b)(I); current on September 13, 2026. ↗
An ordinary sedan has a separate trunk that occupants cannot access from their seats. Is that trunk part of the passenger area defined in Colorado’s alcohol-container rule?
Correct answer: No. It is outside the seating and readily accessible passenger area.
The defined passenger area consists of seating and areas readily accessible from seating positions. The isolated trunk in this scenario is outside it; that does not excuse drinking or impaired driving.
Source: Colorado Revised Statutes 2026, section 42-4-1305 (1)(d) and (2)(a); current on September 13, 2026. ↗
In an ordinary private car traveling on a public highway, an adult passenger uses marijuana. Does being a passenger make that consumption lawful under the vehicle rule?
Correct answer: No. The passenger-area prohibition also covers marijuana use.
The rule prohibits knowingly using or consuming marijuana in the passenger area on a public highway or its right-of-way, subject to specific exceptions. Ordinary private-car passengers do not receive a general exemption.
Source: Colorado Revised Statutes 2026, section 42-4-1305.5 (2)(a)(I); current on September 13, 2026. ↗
For Colorado’s statutory open-marijuana-container definition, a container holds marijuana, has an open or broken seal, and has had some contents removed. What additional element is listed?
Correct answer: Evidence that marijuana has been consumed within the vehicle.
All the listed elements, including evidence of consumption within the vehicle, appear in the marijuana-container definition. Do not substitute the different alcohol-container definition. Marijuana use in the passenger area is separately prohibited.
Source: Colorado Revised Statutes 2026, section 42-4-1305.5 (1)(c)(I)-(III) and (2)(a)(I); current on September 13, 2026. ↗
A traveler finds an exception in Colorado’s statewide open-container law. Does that state law prevent a city from applying an open-container ordinance that is more restrictive?
Correct answer: No. The state law allows local ordinances that are no less restrictive.
Both the alcohol and marijuana vehicle-container statutes preserve authority for local ordinances that are no less restrictive. A limited state exception is not a blanket exemption from local rules.
Source: Colorado Revised Statutes 2026, section 42-4-1305 (3); 42-4-1305.5 (3); current on September 13, 2026. ↗
