Colorado Springs Criminal Law Blog

To determine an individual’s sobriety, highway officers use what is known as the Standardized Field Sobriety Test (SFST). The SFST is a combination of three exams conducted and judged by police officers in a uniform method to secure evidence of an individual’s potential intoxication or impairment and to gain “probable cause” for an arrest. The three exams are the Horizontal Gaze Nystagmus (HGN), the Walk-and-Turn (WAT) and the One-Leg Stand (OLS).

Horizontal Gaze Nystagmus
Nystagmus is the spontaneous jerk of the eye that happens inherently as the eyes move from side to side. When a person is intoxicated by alcohol (and numerous drugs and controlled substances), this movement is typically exaggerated. An officer will test for this by asking a suspect to follow an object with their eyes as it moves across his or her field of vision.

Walk & Turn
For this test, a person is told to take nine steps, toe to heel, in a straight line. After completion of those steps, the individual is asked to pivot on a single foot and walk back to the point of origin in the same fashion. Officers judge impairment based on factors including:

• Lack of attention;
• Failure to maintain balance; and
• Failure to follow physical instructions in an exact or satisfactory manner.

One Leg Stand
In this component of the SFST, the suspect is asked to stand on one foot (with the other about six inches from the floor) and count by thousands (one thousand one, one thousand two, etc.) until instructed to stop by the officer. This test is typically administered for around 30 seconds, and officers may judge based on physical mistakes or counting errors.

Of course, there are many personal conditions that do not involve impairment that may inhibit a person’s ability to perform these tests. For experienced DUI representation in Colorado Springs, contact the Colorado drunk driving lawyers with the Bussey Law Firm, P.C. at (719) 475-2555 for a free case review.

Preliminary breath testing, or PBT, is often used during a traffic stop by an officer who suspects that a driver may be driving under the influence of alcohol (DUI), but who does not yet have enough information to make an arrest. A driver whose PBT results show that his blood alcohol concentration (BAC) is over 0.08 percent may face arrest and charges of drunk driving. With so much at stake, it's important to understand how PBT instruments work.

There are three basic types of preliminary breath testing instruments: infrared, wet chemical, and electrical. Each is designed to take a breath sample and calculate the amount of alcohol it contains, but the methods used may differ.

In an infrared PBT device, an infrared beam inside the device is calibrated to “see” alcohol molecules in a breath sample. The device measures the number of alcohol molecules it can “see” versus the total number of molecules in the sample, and then calculates a percentage. A wet chemical device, on the other hand, measures alcohol in a breath sample by measuring the amount of the sample that reacts with chromate salts, which will react to alcohol but not to most other substances commonly found in human breath.

Finally, electro-chemical or other electrical-based PBT devices, also use a reaction between alcohol and another substance. However, in these devices, the alcohol's reaction with the substance produces an electric current, which the device reads. The stronger the current, the more alcohol is in the breath sample.

Understanding how PBT devices work is just one step in fighting for the best possible outcome in your case. At The Bussey Law Firm, P.C., our experienced Colorado DUI defense attorneys are familiar with PBT technology. They know how to examine test results and other evidence in your case thoroughly and how to build an aggressive defense on your behalf. For a free and confidential consultation, call us today at (719) 475-2555.

Police officers in Colorado and elsewhere use three standardized field sobriety tests along with other clues to help them decide whether or not to arrest a driver on suspicion of driving under the influence of alcohol or drugs (DUI). These tests include the horizontal gaze nystagmus test, the one-leg stand test, and the walk-and-turn test.

These tests are difficult to pass, even if a driver is sober. However, police continue to use them because their ability to pick out drivers who are actually impaired is rated quite high by authorities such as the National Highway Traffic Safety Administration (NHTSA). For instance, a 1998 study cited by NHTSA concluded that in 88 percent of cases, the horizontal gaze nystagmus test will correctly identify an impaired driver; in 79 percent of cases, the walk-and-turn test will correctly identify a drunk driver; and in 83 percent of cases, the one-leg stand test will correctly identify a drunk driver. Overall, the study concluded, the standardized field sobriety tests will correctly identify drunk or impaired drivers 91 percent of the time if all three tests are used together.

Although “91 percent accuracy” sounds impressive, it hides the fact that, even at that rate, one in every ten drivers will be improperly arrested on suspicion of impaired driving when they are not actually impaired. The numbers are even worse if only one or two tests are given. For instance, one in every five drivers will be improperly arrested if only the walk-and-turn test is used.

Field sobriety tests are meant to give officers more information, but a failed test does not automatically justify a drunk driving conviction. If you are facing DUI charges in Colorado, the experienced Colorado Springs DUI defense attorneys at The Bussey Law Firm, P.C. can help. For a free and confidential case evaluation, call us today at 719-475-2555.

Breath testing machines are commonly used to estimate a person’s blood alcohol concentration (BAC) before an arrest. Colorado law enforcement officers typically use an Intoxilyzer 5000, which is a particular brand of breath-testing machine.

All breath testing machines work on the principle that alcohol, once it’s ingested, enters the bloodstream through the walls of the digestive tract. Once it’s there, the alcohol travels with the blood throughout the body, including into the lungs, where the blood drops off carbon dioxide and picks up oxygen as you breathe. Some of the alcohol in your blood leaves the body as you breathe out, along with the carbon dioxide.

The Intoxilyzer uses infrared (IR) spectroscopy to sense the number of alcohol molecules in a breath sample. Since alcohol molecules have a different weight and shape than carbon dioxide or any other molecule in human breath, the IR spectroscope inside the Intoxilyzer machine can be calibrated to “see” these molecules while ignoring others in the sample. The machine then measures the number of alcohol molecules it “sees” against the total sample size to determine what percentage of the sample is alcohol. This number estimates the percentage of the test-taker’s blood that is alcohol. A person with a BAC percentage of 0.08 or higher is prohibited from driving under Colorado law.

The Intoxilyzer is a piece of precision equipment that must be calibrated, tested, and maintained regularly in order to give accurate test results. If you have been charged with drunk driving in Colorado, the experienced Colorado DUI lawyers at The Bussey Law Firm, P.C. can help you build an aggressive defense that fights for the best possible outcome in your case. For a confidential consultation, call us today at 719-475-2555.

The final judgment on a DUI case isn’t always the end. Colorado realized this in December 2009 when the Colorado Springs Police Department announced that chemist error had inflated blood alcohol content results for, at the time of their announcement, 82 drivers at the Metro Crime Lab.

The flawed DUI tests in Colorado Springs caused quite an uproar, especially for drivers who had been convicted of a DUI between 2007 and 2009. Once this announcement was made, Timothy Bussey of The Bussey Law Firm, P.C., received several calls from clients who were concerned about their cases.

To get to the bottom of the matter, Mr. Bussey filed a request for a Colorado Open Records Act. Although Mr. Bussey did not receive all the information he had hoped, he was, nevertheless, provided with some very useful information. The disclosed information proved that chemist error was the reason for the inflated BAC results. The investigation concluded that a total of 206 DUI tests had been faulty. Of these, nine cases were affected.

With the help of a dedicated DUI defense lawyer, the Colorado Springs Metro Crime Lab situation was identified, contained, and rectified where possible. The following actions were taken to repair the situation:

1. Charges were dropped or reduced;
2. Refunds were issued for court fees;
3. The forensic chemist responsible was no longer employed by the Colorado Springs Police Department;
4. The Metro Crime Lab voluntarily relinquished their DUI testing certification; and
5. The police department would conduct stricter proficiency exams for chemists in the future.

If you have been charged with a DUI in Colorado as the result of a faulty BAC, experienced Colorado Springs DUI defense lawyer, Timothy Bussey, will investigate the details of your case and help you build a strong defense. Mr. Bussey has a critical understanding of the science behind the Colorado DUI investigation process. He has years of experience both in prosecution and defense of DUI cases, which he uses to ensure that his clients are treated fairly. Contact Mr. Bussey today at (719) 475-2555 for a free and confidential consultation.