Document Type

Supreme Court Commentaries

Publication Date



Fourth Amendment, Warrantless Searches, Blood Alcohol Concentration, Search incident to arrest

Subject Category

Constitutional Law | Supreme Court of the United States


In Birchfield v. North Dakota, the Supreme Court explored warrantless breath tests during DUI stops and their validity under the Fourth Amendment. To determine their constitutionality, the Court adopted a balancing test, weighing the government’s interest in preventing instances of drunk driving with the intrusion on an individual’s privacy. The Court ultimately concluded that warrantless breath tests are constitutional when conducted incident to a lawful DUI arrest. This commentary explores the Court’s reasoning and holding and will argue that the Court was correct in deciding that a warrant is not necessary for conducting a breath test incident to a lawful DUI arrest.