Everything You Need to Know About Blood Testing from DUI Attorney Tim Bussey

Everything You Need to Know About Blood Testing from DUI Attorney Tim BusseyMany people believe that a DUI blood test is infallible; and that by submitting to a blood test, you’re automatically convicted. This couldn’t be further from the truth. Colorado DUI attorney Tim Bussey explains the possible defense strategies that can be used against a blood test.


In Colorado, when you’re charged with a DUI, there’s really three options that you’re looking at: blood, breath, and refusal. I want to talk a little bit about blood testing. When a person submits to a blood test, a lot of people think that their blood is actually just going to be tested, that somehow it’s going to go into some machine, that it’s going to be analyzed and a result’s going to come out and there’s no way that there can be an error in the testing. Blood testing relies upon humans, and with humans, there can be something called human error.

On a DUI case typically, a person who submits to a blood test will be taken to a hospital. It doesn’t necessarily have to be in a hospital, but typically that’s the way it goes. They have someone come out that is often referred to as a phlebotomist. It is typically a technician that works at the hospital, who’s called out by the police officer, who pulls the blood out of your arm, and that blood is then sent to a laboratory for an analysis.

It’s important to know that there needs to be a chain of custody that exists on that blood. You need to be able to track that blood from the time that it was pulled. You need to ensure that it was pulled in conformity with the Colorado Department of Public Health and Environment rules for obtaining that blood, and that it was tested in accordance with the rules by the Colorado Department of Public Health and Environment.

What they use, or what laboratories use to test blood, is something called a gas chromatograph, and you’ll often see if you get the results, it’ll say “GC,” which stands for gas chromatograph, with “FID,” “flame ionization detection.” It’s a process that they use to test the amount of alcohol that’s in the bloodstream.

Here in Colorado, they have to do it in conformity with rules established by the Colorado Department of Public Health and Environment. What happens is that when the blood is pulled, it is typically placed into a kit and it’s shipped to a lab. There are different labs that are used by different law enforcement agencies here in Colorado, but it’s important for a person to know that they’ve hired an attorney that knows how this testing works. Because when you get your discovery, the discovery will include gas chromatograms, which is the actual testing data.

I have been to classes where I am taught what to look for concerning those gas chromatograms. Essentially, what you’re looking for is separation on those chromatograms that will show peaks that will look like a graph to show how much alcohol is in a person’s system. With that, I will be taking a look at the discovery to see if there are any errors that are apparent on the paperwork concerning a blood test. I do have experts that can look at this, forensic toxicologists that do testing for a living and sometimes I’ll ship it out to them, but I can at least speak the language with them to understand that when it comes to blood alcohol testing.

Blood alcohol testing uses head space gas chromatography, so they’re actually testing the gas above your blood. They’re not actually dipping in and shooting your blood into some magical machine, it just doesn’t work that way. But there is protocol that exists concerning blood alcohol testing. There is a chain of custody requirement to track that through. Errors have occurred on blood alcohol testing. I don’t know if any particular client when they come in and seem me is going to have one of those errors, but it has occurred. I can anticipate that it is going to continue to occur, and it’s important to have an attorney that understands the science behind blood alcohol testing advocating for a client.

An experienced Colorado DUI attorney can help you understand your legal options when getting a blood test for a DUI charge. For more information, contact our team at (719) 401-0585.

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