How Many Drinks Before You’re Over the Legal Limit in Colorado?

Categories: DUI Defense

Alcohol and key symbolizing number of drinks before over legal limit in Colorado.

This is an incredibly common question. Most people know that the legal blood alcohol concentration limit for drivers is .08%. If an officer pulls you over and asks you to take a breath test and that test shows a blood alcohol concentration (BAC) of .08% or greater, buckle up—you are about to be escorted to jail and charged with DUI.

This is true even though people absorb and metabolize alcohol at significantly different rates. Maybe you are a large man who has built up a tolerance to alcohol and does not feel at all impaired at .08%. Full-fledged alcoholics may not even feel mildly buzzed at this level. But the law says that your actual impairment level does not matter once you hit .08% BAC or greater. That is DUI “per se” and is illegal by definition. So how do you know when you reach that level? The answer is not a short one, neither is it precise. But let’s dive in and see what factors to consider when deciding whether it is safe to drive.


Every person is unique. So if two people drink the exact same amount of the exact same liquor over the exact same period of time, their BAC levels and actual impairment levels can be significantly different. Here are just some factors that affect these levels:

  • Your gender;
  • Your age;
  • Your weight;
  • Any tolerance you have to alcohol;
  • Whether you’ve eaten food while drinking;
  • Water consumption or hydration level;
  • The alcohol content of your drinks;
  • How long you’ve been drinking;
  • Fatigue;
  • Prescription medications you’ve recently taken;
  • Over-the-counter medications you’ve taken; and
  • Illegal substances you’ve ingested.

These and additional factors can make a big difference to your actual level of impairment and BAC reading.


Colorado law defines DUI as .08% BAC or higher and DWAI (driving while ability impaired) as .05%-.079% BAC. As discussed above, law enforcement can charge you with DUI if your BAC is .08% or higher, even if your driving was not problematic or dangerous. However, an officer can charge you with DWAI even if your BAC is below the threshold of .05%. In Colorado, officers can make a DWAI arrest if they believe that your driving ability is even slightly impaired, regardless of BAC levels. If an officer charges you with DWAI even when your BAC is below the threshold, contact an experienced DUI legal practitioner immediately. An officer’s observations are subjective and can be inaccurate.

For instance, suppose an officer assumes that you’re impaired because your eyes are bloodshot and your speech is slurred. So even though your BAC was .04%, she arrests you for DWAI. In this scenario, you may have a valid defense. Your bloodshot eyes may result from allergies, and you may have a slight speech impediment that the officer never considered.

But in this same scenario, suppose the officer arrests you because of the aforementioned observations and the fact that you weaved in and out of traffic. They can arrest you if your driving is “even slightly impaired.” But how does the officer know that weaving in and out of traffic isn’t a habit of yours? How does she know that this action exhibits slight impairment as opposed to simple bad driving habits? Again, the observations are subjective, and you may want to consult with an attorney in this type of scenario.

Blood Alcohol Levels

Now let’s move on from impairment to BAC levels. How do you know when your BAC has reached the threshold that can land you in jail? Unfortunately, there is no one-size-fits-all answer to this question. But to play it safe, here are some general rules you can stick to.

Rule of Thumb

The general rule of thumb is that you should not drink more than two drinks in an hour to stay out of the danger zone. For our purposes, a drink is either:

  • 1 ounce of hard liquor;
  • 12 ounces of beer; or
  • 5 ounces of wine.

Most people (but not all) are safe if they drink only two drinks in an hour or less. However, keep in mind that if you drink two drinks per hour for 4 hours, the accumulated alcohol can land you at a much higher BAC reading. It all depends on how quickly your body metabolizes alcohol. So if you want to be sure, space your drinks out over time. For instance, if you drink two drinks in one hour, maybe wait an hour before having another.

Effects of Varying Blood Alcohol Concentrations

Even though legal blood alcohol concentration limits are bright lines in the sand, so to speak, how these levels affect us varies. But here are some symptoms you can watch out for while drinking. Although they are far from fool-proof, these typical symptoms can give you at least a rough idea of where you fall on the spectrum.

  • .02%: For drivers under 21 years old, this is the legal limit. Light to moderate drinkers typically feel some effects.
  • .04%: Your inhibitions typically begin to lessen at this point, and relaxation sets in.
  • .06%: Your mental acuity and judgment begin to wane.
  • .08%: This is the legal intoxication limit. Intoxication sets in, negatively impacting your motor skills and driving ability.
  • .10%: Your reaction times and reflexes slow down significantly. It is no longer safe for anyone to drive at this level.
  • .12%: You will likely begin to feel sick, nauseous, and possibly vomit at this stage—unless you are a regular drinker who has built up a significant tolerance level.
  • .15%: At this stage, you will experience problems with balance or “the spins.”
  • .15-.25%: This is the level where blackouts begin to happen.
  • .30%: This is now a medical emergency where most people lose consciousness.
  • .40%: At this level, it is rare not to lose consciousness, and many people die.
  • .45%: At this point, breathing stops, and death occurs.

When drinking, keep in mind that alcohol enters the bloodstream quickly. It seeps into the blood through your small intestine and stomach in as little as 15 minutes. You get drunker the more you drink and don’t forget to take factors like age, weight, and food consumption into account.

We’re Here for You!

While there is no exact science to provide you with complete peace of mind, the above markers can help you track where you are on the spectrum when drinking. Even if you buy a hand-held breathalyzer device, there is no guarantee that it is calibrated to precisely match what law enforcement finds when they test you. Always err on the side of caution. And if you get arrested, call the experienced lawyer at Mark S. Rubinstein, P.C., right away. We know Colorado DUI’s and can protect your rights every step of the way. Call or contact us online today.

Mark Rubinstein

Attorney Mark S. Rubinstein has been practicing law for more than 30 years, including 25 years in Colorado. He founded Mark S. Rubinstein, P.C., in Carbondale after working for law firms in Denver and earlier in his career in San Diego. He focuses his practice in the areas of criminal defense and personal injury representation, and he is well known throughout western Colorado as an effective and unwavering advocate for his clients.