That is the question before the U.S. Supreme Court
, as 3 drivers charged with drunk driving were also with the separate crime of violating their states’ “No Refusal Law”. Missouri is in the vast majority of states which have so such law that says it’s a separate crime to refuse to take a breathalyzer. But the drivers in the case now before the Supreme Court are from North Dakota and Minnesota, two of thirteen states which currently have “No Refusal” laws on the books.
You may recall this blog discussing a similar case before the Supreme Court (in 2012) featuring a Missouri case
. In it, the Court declined to issue a bright-line rule that breath tests can be conducted in every drunk driving arrest without a warrant. The lawyers pushing for these laws to stay in tact (and perhaps become more widespread) are arguing that such tests can be conducted without a warrant under the 4th Amendment's "search incident to arrest" exception. They also argue that the 4th Amendment only bans "unreasonable" searches, and that a quick breathalyzer test or blood draw is "reasonable". Absent that, there is also the commonly used argument that by being issued a license to drive on state roads, you implicitly consent to a test to determine your BAC.
Most experts believe that these laws will be upheld, and that some states - which have been waiting on guidance from the Supreme Court as to how they will rule - may enact similar laws if a decision is made in favor of the laws. A final decision is expected in June.