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How Blood Tests Work in DUI and DWI Cases

If you have been pulled over for DUI or DWI the police officer will ask you to submit to a breath test or you may end up taking a blood test to measure the blood alcohol content (BAC) in your body.   Your BAC reading is one of the key pieces of evidence that the prosecution will use in proving that you were driving drunk.  If a blood test is used to measure your BAC, it is important to understand what this test measures, how it administered and what can affect the results.

Police officers now have devices in their vehicles, known as breath testing equipment, that measure breath alcohol levels in suspected drunk drivers.  However, if you are being accused of DUI or DWI and believe that the breath analysis is not accurate, you should be able to request a blood test.  Keep in mind though, a blood alcohol test measures the amount of alcohol in the blood at the time the sample is taken and does not reflect your BAC at the time you were driving.  If you have been drinking alcohol, your blood alcohol level will go up over time and is at its highest about one hour after you have consumed alcohol.  Typically, the body is able to break down about one drink per hour.

Blood alcohol tests are performed to check for intoxication.  If a police officer observes you acting confused, unsteady or driving erratically, a blood alcohol test is used to show the amount of alcohol in your system.  A blood test is administered at a health care facility by a medical professional.  Basically, the medical provider will be drawing a sample of your blood to test your BAC.

There are some factors that can affect the results of your test.  According to an article posted on Yahoo! Health, if rubbing alcohol was used to clean the skin before the needle was inserted, the results may not be useful.  If you have high blood ketones, which can result from diabetic ketoacidosis, the test may not accurately reflect your blood alcohol content.  Also, if you have taken cough medicines or herbal supplements that contain alcohol, such as kava or ginseng, you may have an inaccurate BAC reading.

If you have been accused of DWI or DUI, you need to contact an attorney immediately.  There are legal defenses available, especially if the results from your blood alcohol test were inaccurate.  Call 1-888-DWI-ANSWER or 1-888-DUI-ANSWER today.