The question continues to be asked following the Supreme Court decision earlier this year, which addressed the same question.
In three separate cases, drivers in Minnesota and North Dakota who were suspected of driving under the influence were told they must comply to either breath or blood tests. When a North Dakota driver refused the blood test without a warrant, that driver was charged. The court was asked if these tests administered without warrants were constitutional.
The first part of this quandary involves implied consent. Implied consent means essentially that any driver on the road agrees to be tested for drunk driving if there is probable cause. Implied consent is recognized in all 50 states.
The second part of the argument involves the Fourth Amendment. The question here is whether the police have the right to a "search and seizure" of your breath and your blood without a warrant.
Breath tests deemed not as invasive as blood tests
The court decided that compelling a driver suspected of drunk driving to take a breath test without a warrant is not a violation of the Fourth Amendment. A breath test, in the opinion of the court, is not a violation of personal privacy.
However, the court found that taking a blood sample without that driver's consent and without a warrant is in violation of the Fourth Amendment, as it violates a person's right to privacy. First, because a blood sample is retained (whereas a breath sample is not) and second, because a blood sample holds much more information about a person than just blood alcohol content.
The court therefore found breath tests nonintrusive whereas blood samples are found to be intrusive.
What does the Supreme Court decision mean for motorists in Indiana who are stopped by police? Indiana courts and the Indiana Bureau of Motor Vehicles (BMV) can punish drivers for refusing a breath test following a DUI arrest, but do not submit to a blood test after a DUI arrest unless police present a warrant.
It is likely that police officers will resort to giving breath tests, possibly with a warrant, and fewer will attempt to compel drivers to take a blood test.