Police departments across the United States are beginning to mandate that those suspected of driving under the influence (DUI) take an automatic blood test to determine their blood alcohol content (BAC). This is contrary to the traditional and widely used breathalyzer test. Currently, Michigan uses the DataMaster to test DUI suspect’s breath, and blood is usually drawn when the motorist refuses to submit to the breath test.
While blood tests have several law enforcement advantages, blood test results take much longer to process than does a breathalyzer test. In Michigan the alcohol blood test in a drunk driving test usually takes about two weeks, but it can take much longer. It takes longer still before the prosecutor and the accused learn of the blood test results.
Another law enforcement advantage with a blood test in a drunk driving case is that a breathalyzer tests cannot detect the presence of drugs in a person’s blood stream, but blood tests can. (Eiserer). If in fact drugs are present, this may make prosecution for drugged driving a viable option. Additionally, a 2008 federal study found that it results in more defendants pleading guilty, fewer cases going to trial and increased conviction rates.
Some police departments are still considering blood tests as the only option to obtain a suspect’s BAC. Many officers are being trained across the county to draw the driver’s blood. In some states, such as Arizona, police officers are actually trained to (themselves) draw blood at the roadside.
However, blood tests also create many additional legal challenges that do not exist with breath test cases, some of which can even lead to charges being dismissed. This is why many departments haven’t fully committed to this option yet.
With the accuracy that blood test results purport to provide, more and more DUI accused are taking a plea and not going to trial. This can be a costly mistake. If you have been charged with a Michigan DUI then it is important to discuss blood test defenses with your attorney. You may have defenses with the blood test result that would not exist with the breath test.