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Drunk Driving Defense
Blood Alcohol Content
Michigan has very strict driving under the influence (DUI) laws. A driver with a blood alcohol content (BAC) of .08 percent or higher is considered over the legal blood alcohol limit. A driver with a commercial driver’s license (CDL) with a BAC of .04 percent or higher can be arrested for DUI.
A driver under the age of 21 may be arrested for DUI if he or she has a BAC of .02 percent to .08 percent. This is commonly known as the Zero Tolerance law.
How Is Blood Alcohol Content Determined?
In Michigan, BAC is determined by breath, urine or blood test. The implied consent law says that a driver automatically agrees to submit to a chemical test whenever he or she operates a motor vehicle. The driver does not have the option to refuse the test in Michigan. Refusal will result in a one-year driver’s license suspension and six points on the driving record. Officers must advise drivers of their chemical test rights and the consequences of refusal.
There are several methods for determining BAC, including:
- Breath test: Police officers most commonly determine BAC level with a chemical breath test using a Breathalyzer. In Michigan, the Breathalyzer is called the Datamaster or Datamaster DMT. The officer must follow specific procedures before having a driver blow through a tube into the Breathalyzer. Errors are commonly seen with the use of the devices. The errors may cause false BAC results.
- Blood test: Officers typically use blood tests if the driver is injured, unconscious or has refused to take the breath test. A blood test may be obtained with the driver’s consent or with a search warrant based on probable cause.
Chemical test results are presumed to be the BAC at the time the driver was operating a motor vehicle. A DUI attorney will examine the test used and the results. Mistakes may have been made during the testing process.