Blood, Breath, or Refuse


Chances are that if you are attracted to this article title, it may be too late for it to make a difference to you. Deciding whether to do a blood alcohol test, a breath alcohol test, or to refuse a test altogether is usually only considered by people AFTER they have already made that decision and been charged with Driving Under the Influence (DUI) or Driving While Ability Impaired (DWAI). Still, it is an interesting discussion. Let me start with a little background.

The Basics of Blood Alcohol Content (BAC)

Let us start with the basics. The more alcoholic beverages a person drinks, the more intoxicated they become. While individual differences between people such as whether male or female, body weight, natural and developed tolerance, and how recently they ate can affect the absorption rate of alcohol and the level of intoxication, years of scientific studies have taught that certain levels of alcohol tend to impair one’s motor skills, reaction time, judgment, comprehension, and general ability to safely operate motor vehicles.

BAC and Prosecution of DUIs

Prosecutors find it much easier to convince juries that an individual was impaired by alcohol and intoxicated if they are able to demonstrate a BAC level (Blood Alcohol Content) to the jury. BAC is essentially the amount of alcohol, or the blood alcohol concentration, in someone’s bloodstream. A high blood alcohol level indicates a high level of intoxication. While the observations of police officers, such as issues with coordination, judgment, admissions to drinking beer or a glass of wine, or even vomiting are useful in convincing a jury that someone was intoxicated while driving and was suffering the effects of alcohol, a scientific BAC test demonstrating the level of ethanol in the bloodstream is extremely useful in demonstrating that any impairment was due to consuming alcohol. Evidence of a defendant’s actual BAC simply makes their job much easier, and makes the successful prosecution of a DUI case much more likely.

Because a test showing a person’s BAC level can be so essential to securing a DUI conviction, the Colorado state legislature has written laws making it costly for a DUI suspect to refuse to take a blood or breath test. Colorado’s express consent statute dictates that, by the act of driving on the roads of Colorado, you have already agreed to take a blood or breath test if a police officer determines that there is probable cause that you are driving under the influence of alcohol.

Colorado Express Consent

In Colorado, because of the express consent law, when someone is arrested for DUI or DWAI, the driver is faced with three options—choose a blood test, a breath test, or refuse to take a test. After making this decision and hiring me, my clients often wish to know which test I prefer from a defense attorney’s perspective. Well—full disclaimer–while defending DUI clients may help me pay my mortgage, my honest preference would be that there was no reason anyone would suspect my clients of driving under the influence in the first place. Wishful thoughts aside, it is an interesting discussion. While attorneys differ this issue—I do definitely have my own perspective. But before I go into my preference as a DUI attorney, let’s review what each of these separate choices entail.

The Three Options

In Colorado, once an officer has probable cause that someone is DUI, they must advise the driver of Colorado Expressed Consent. This advisement boils down to a simple choice: either a driver agrees to take a blood or breath test to determine their Blood Alcohol Content (BAC), or they lose their license if they refuse such a test.

Breath Test

If a driver chooses breath, they will be taken to a nearby police station for a test using an intoxilyzer machine (commonly called a Breathalyzer). The officer will observe the suspect for 20 minutes to make sure that they do not belch or perform any other bodily function that could result in stomach contents entering the mouth—as this can result in a severely inaccurate test result. After that twenty-minute observation period, the driver must blow into the intoxilyzer as instructed by the officer. There is then an additional two-minute pause before the officer has the driver blow into the tube again. If the results of the two “blows” are not within a certain margin of error of each other, the test is invalid. However, if they are within that range, the machine selects the lower of the two values as the reported value. If the BAC result is higher than .08, the driver’s license will be immediately suspended, and the driver will have only 7 days to request a hearing to challenge that suspension (it may be an uphill battle—but always request a hearing!!!) Additionally, you will find yourself with a summons for Driving Under the Influence.

Blood Test

If a driver chooses a blood test, they will be taken to a nearby hospital for a blood draw. A certified phlebotomist (person who can draw blood) takes two vials of blood. The officer then (hopefully) properly seals and labels the vials. The vials are sent to the CDPHE lab in Denver (in most instances, although some agencies do use an independent lab) to be tested. This can mean that it is quite sometime before the blood results are available on a case. The law enforcement test itself uses only one vial, the second vial is available for potential retest by an independent lab at the defendant’s/defense attorney’s request. The driver keeps their license pending the results of the blood test. However, even though the officer will not yet have the results, he or she will still write you a summons for DUI or DWAI. After all, they could not have required you to take a test if they did not have probable cause to arrest you for one of those charges. The results of the blood test, if they come back higher than the legal limit, will simply serve to greatly increase the strength of their case against you.


If a driver chooses to refuse to take either type of test, they will still be charged with DUI, and their license is immediately suspended. This suspension can be challenged at a hearing in front of a hearing officer from the Division of Motor Vehicles, which must be requested within 7 days as mentioned above. (It is very important to note that a driver only has 7 days from the date of the charge to request a DMV hearing!!! Do not forget to request this hearing!)

Which One Is Best?

So, having learned the options, which choice should you make if presented with the situation? Again, many attorneys differ on this issue and most acknowledge there is no clear rule, particularly because each situation is different. However—as I am the one writing this article, I feel comfortable in giving you my general preference. I prefer my client’s to choose a blood test. Let me explain.

As an attorney, I cannot retest a breath test to make sure the result was accurate. While I am able to review some maintenance records for the particular intoxilyzer unit used as well as calibration and self-check records, the fact is that it is very hard to challenge what is essentially a magical box that spits out a number. In trial, I cannot cross-examine a box . And I cannot retest the sample to see if the number spit out by the magical box was correct. While the process of getting an accurate BAC result is complex and subject to real and common errors, jurors seem to think that the number issued by an intoxylizer is as reliable as that shown on their electronic speedometers on their drive home each evening. Everyone understands human error—but without any humans to question regarding error, jurors assume there is none. As a defense attorney, I don’t like a result from a magical box that I can’t verify or impeach in cross-examination in front of a jury.

Well, what about just refusing a test altogether? One might think that, despite the driver’s license repercussions, choosing to refuse a test would be the best option. However, in Colorado, the District Attorney is permitted to argue in trial that there is only one reason that someone would refuse to take a test that could prove their innocence—namely that they knew they were guilty. The Fifth Amendment implications of this aside for a moment—this is a difficult argument for a defense attorney to counter unless there really was an unusual circumstance that helps explain the alleged refusal. It is also important to note that, at least in El Paso and Teller counties, Deputy District Attorneys typically will not offer deferred sentences on refusal cases as they themselves do not know how intoxicated the defendant really was. Thus, a refusal can make a good plea offer more difficult to obtain, especially for a first offense.

Finally, there is the blood test option. I like blood tests. I can retest blood. I can have an independent certified lab double-check the results. If the lab comes back with a lower result, at the very least I can try to use that lower result in plea negotiations. If the case goes to trial—I can demand the presence of the lab technician that tested the blood and submit the technician to cross-examination. I can also obtain a virtual pile of paperwork on how the test was conducted and the results to see if there were any errors or abnormalities present in the underlying data. Moreover—law enforcement blood labs in Colorado have had a virtual perpetual cascade of personnel and methodology issues (some would say scandals) over the last several years that can be brought to the jury’s attention during a trial to challenge the test results. With a blood test—there is simply more for me, as a criminal defense and DUI attorney, to work with. No doubt there are some cases where I might wish my clients had opted for a breath test or to refuse a test altogether. However, in general, my personal experience is that blood provides more potential options, and thus a better chance for a good outcome for your case.

If You Are Reading This–You Probably Need a DUI Attorney

If you are reading this—either you are curious about a decision already made, or are planning ahead. If you have picked up a DUI charge and are second-guessing yourself over your choice of test—don’t. First—what’s done is done. Second, even cases with breath tests and refusals can have excellent issues for an attorney to use in getting you a great outcome. If you are reading this because you are planning ahead just in case, please do not drink and then drive. That is always the best plan. While I do need to pay my mortgage, I would prefer you stay safe. However, if you do find yourself pulled over and arrested for DUI, consider choosing a blood alcohol test. In most cases, it provides more options for your attorney to work with.

DUI cases and law can be confusing and complicated. If you are reading this article because you have recently had to make a choice of whether to take a blood test, breath test, or to refuse a test, you likely are facing a DUI charge that can affect your life, career, and liberty. Whether you weren’t driving while intoxicated, were a little intoxicated, or were sloppy drunk, you need the help of a quality DUI lawyer to help you. Our attorneys at Peakstone Law Group, LLC have years of experience in successfully handling cases just like yours. Call us today for a free consultation to find out how we can help you through this.

Life happens. Let us help.