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DUI Breath Tests in Colorado
If you are reading about how a DUI breath test works, you have probably blown into one recently. The breath test is the most common chemical test requested  by Colorado police officers after an arrest for DUI. The Colorado Express Consent Law gives the DMV the authority to revoke a driver's license if they refuse to provide a specimen after an officer requests one following a lawful impaired driving arrest.     

Breath specimens are usually favored by Colorado DUI officers for the following reasons:

1. Convenient. Breath testing machines are located at the police station or jail.
2. Fast results. A breath machine shows the officer the BrAC immediately.
3. Self serve. Certified officers can operate an I 9000 without needing help from any other officer or technician.
4. Harder to attack in court. Officers know that at a DUI trial, it is harder for experts to attack a breath test result
    and there is no ability for a DUI lawyer to independently re-test a breath specimen.

Since 2013, Colorado has used the CMI Intoxilyzer 9000 for DUI breath alcohol measurements. Colorado was one of the first states in the U.S. to move to the Intoxilyzer 9000. The company that sells the 9000, CMI, has been making DUI breath test machines for police for decades. The I-9000 is their newest addition to their line of breath alcohol testing devices.            
Colorado DUI breath test
CMI Intoxilyzer 9000
drug DUI defense
Denver DUI drug defense
Jefferson county DUI drug defense
Police breath test machines are only capable of measuring breath alcohol concentration. The I-9000 cannot detect marijuana or other drugs that may be suspected by a DUI officer. In cases where impairment is believed to be from something other than alcohol, officers will often ask for a blood specimen. In some cases, officers will offer a breath test, and after they see there is no/ little alcohol in the result, they will then request a blood sample to send for lab testing- Colorado law allows this.     
Jim Medley's Expertise in DUI Breath Test Defense

Attorney Jim Medley has been dealing with CMI Intoxilyzer machines since the 1990s. The Intoxilyzer 5000 was in use when Jim was a police officer. The I-5000 was in wide use across the country until the early 2010s when the I-9000 began to be adopted in many states. 

The chemistry and physiology behind DUI breath alcohol testing science has not changed since the 1950s. Alcohol, because it is a volatile, has a gaseous phase at normal temperatures. This causes estimable amounts of alcohol in the bloodstream to diffuse into the air in a person's lungs; the more alcohol in the blood, the more alcohol will be in the breath. Once inside the Intoxilyzer, the concentration of alcohol in the breath is measured using an analytical technique called infrared spectroscopy.

The use of spectroscopy to distinguish volatile organic compounds in not a precise science and it can make mistakes.           

breath test expert
Certified Breath Test Operator
DUI defense specialist

Jim Medley first attended advanced training in alcohol breath testing in early 2004. This forensic course was taught in part by a medical doctor who was board certified in Forensic Toxicology. Attorney Medley obtained hands-on experience operating a CMI Intoxilyzer device and detailed knowledge about the chemistry principles behind how machine works and in what areas the Intoxilyzer results can be questioned.       

Certified Breath Test Instructor
DUI spcialist

By the end of 2004 DUI lawyer Medley attended more advanced training to be an Instructor of evidential alcohol breath testing and in the maintenance of the Intoxilyzer 5000. Jim learned more details about the inner workings of the Intoxilyzer and he also obtained his own Intoxilyzer device to conduct experiments on and study maintenance issues.         

Medley expert DUI breath test

Since 2004, Jim Medley has evaluated several hundred DUI breath test machine service records, and has had results excluded from court that have shown improper maintenance, improper calibration, or improper operation by the officer.          

Attorney Medley working on a CMI Intox. 5000
Master of Science in Forensic Toxicology
DUI expert

Since 2006, Jim Medley has held a Master of Science degree in Forensic Toxicology. The analysis of breath for alcohol concentration is toxicology. Any DUI trial involving a breath test will involve some police employee with a degree in Chemistry or Biology testify that breath tests are accurate and reliable. Your lawyer has to be able to cross examine the police chemist about chemistry ... and win the discussion. Jim Medley is the only Colorado DUI lawyer with an advanced degree in Toxicology.

Colorado's Intoxilyzer 9000
CMI's newest Intoxilyzer is not undefeatable. The newer model did address some of the criticisms that the forensic science community had of the I- 5000. The machine however still suffers from many of the same pitfalls that have plagued DUI breath alcohol testing since the 1950s. Law enforcement still chooses to implement less expensive equipment that is built upon assumptions, averages, and a "close enough for government work" mentality.               
Colorado DMV law
The Colorado Department of Health very recently published a new manual for the operation and instruction of operation for the Intoxilyzer 9000. It is vital that any Colorado DUI lawyer stay current on any changes in police procedures, science, or laws. Attorney Jim Medley has maintained his sharp edge on the forensic aspects of defending breath alcohol test results, and is current on the contemporary angles of attack on these newest DUI enforcement machines used in Colorado.             
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