Breath and blood tests are instrumental when charging and sometimes convicting individuals of DUI. In Georgia, after reading an implied consent statement to the individual garnering their consent, an officer will take that person back to the police department and administer a breath test by asking the person to breathe into a tube.In some instances, an officer might request a blood test, as opposed to a breath test, because of their accuracy. Challenging Atlanta DUI blood and breath tests is impossible without understanding them first. If you want to know more about challenging blood and breath tests, speak to an experienced DUI lawyer.

Science Behind Breath Tests

Knowing the science behind breath tests can help when challenging Atlanta DUI blood and breath tests. The entire State of Georgia uses the Intoxilyzer 9000. The machine will do a calibration check on itself to determine if the machine is within tolerance and then the person will be asked for a second sample. In total, two samples are given.

The machine uses infrared spectrophotometry to detect the presence of alcohol in a person’s blood. In simple terms, light passes narrowly through wavelengths or a chamber when somebody breathes into the breath machine, and the alcohol molecules either reflect the light or do not. The less light hitting the back of the target or the back of the sample chamber, the higher the alcohol level is.

Ensuring the Validity of Intoxilyzer Results

The Intoxilyzer 9000 is checked four times a year, a quarterly inspection, to check interference (whether there is some sort of radio frequency interference that can be detected); determine whether the machine is within tolerance of 0.08 grams of alcohol; whether there is any interference such as acetone or other substances detected; whether there is mouth alcohol present; and whether the machine can register between 0.20 between the two sample tests.

Accounting for Officer Error

A state patrol officer visits the various departments and checks their machines quarterly, and will issue a certificate indicating that all of the machine’s parts are attached and in good working order. There are not many steps officers need to take in order to ensure the validity of the breath test they are administering. Georgia is pretty lax on that particular requirement. If an officer can get two samples 0.20 grams apart, that is it. There are no real rules, which is important to keep in mind when challenging Atlanta DUI blood and breath tests. Any difference or variation would go to weight, not the admissibility of a test.

Challenging the Results of a Roadside Breath Test

There is no challenging the results of a roadside breath test. An officer can only testify whether it is positive or negative. The only way to challenge is to contest if an officer can testify to that is whether they are familiar with the device and if it is a device approved by the Georgia Bureau of Investigation, Division of Forensic Sciences. If so, then the Officer can testify that the results are positive or negative, but, an Officer cannot give a numerical value for what a person blows on the side of the road.

When an Officer Can Request a Blood Test

If an officer has probable cause to believe that a person is under the influence of alcohol or drugs, they will subsequently arrest the person, read them the implied consent, and then have the choice to ask for any type of test that they choose, blood, breath or urine. That being said, an officer can choose to ask for a blood test. Officers generally will ask for blood when drugs are involved.

A blood test can be given basically anywhere. It needs to be drawn by a person who is qualified to draw blood, e.g., a phlebotomist, a medical assistant, a nurse, an EMT; somebody who has a specific education on how to draw blood. Georgia requirements are fairly stringent on who can draw blood, but it is not that difficult to get it.

Accuracy of Blood Tests at Determining BAC

When challenging Atlanta DUI blood and breath tests, it is important to keep in mind that historically, blood tests are more accurate than breath tests, because a breath test is an indirect way of trying to measure how much alcohol is in somebody’s blood. However, blood testing is not perfect. There are different types of interference that can be construed as alcohol. The machine has to be properly calibrated. Blood testing alone, simply seeing a result on a piece of paper, is not conclusive in and of itself as a determination of how much alcohol is in somebody’s body.

Refusing Blood Tests

Blood tests cannot necessarily determine impairment, they can only determine the quantity of what is in somebody’s blood and specifically which drug is in somebody’s blood. The law does not have any justifiable reasons for refusing a blood test except in DUI cases. A person can refuse and has every right to refuse, a blood draw for whatever reason. That is not a legally justifiable defense, but a person can refuse a blood test for whatever reason they want. The state can get a warrant and forcibly remove blood if needed.

Steps a Lawyer Can Take to Challenge a Blood Test

If an attorney wants to start the process of challenging Atlanta DUI blood and breath tests, the first thing they will need to do is get a litigation package, if they can, from the Georgia Bureau of Investigation (GBI).

The litigation package will allow the attorney to see the results that were tendered by the state, the chain of custody, how the blood was kept, who drew the blood, see the gas chromatograms that determine the measurements of how much ethanol or alcohol is in somebody’s blood.

Essentially, in Georgia, there are several tests performed and the GBI will average the two, giving a blood alcohol number. However, looking at a piece of paper and seeing a number is not conclusive that the test is 100 percent correct. If you wish to challenge a blood or breath test, speak with a qualified attorney that can help.