When you have been arrested for suspicion of a Los Angeles DUI, officers will ask you to take a field sobriety test at the scene of the arrest. This test is not mandatory, and is voluntary. This means that you do not have to submit to it, and there are no consequences. However, if you are arrested, you will be required to take one at the station. This test can be a breath test, or a blood test. There used to also be a urine test option but that is no longer the case.
Oftentimes people do not want to take the breath test and opt for the blood test. For example, they may have asthma and are unable to blow hard enough into the breathalyzer machine. If they opt for the blood test, then those results will be provided in two weeks.
However, in certain situations people refuse to take either test. They may have a fear of needles, or they may simply not agree to submit to a test. If you refuse to take either test, it could be categorized as a refusal, and a refusal will be considered an aggravating factor when and if you are sentenced for a DUI. This means that the sentence will be on the higher end of the range, or will have added sentencing because of the refusal or take a test. It is viewed as being uncooperative.