This post is a continuation of a previous blog post. To read that post, click here.

The Supreme Court decided in Birchfield v. North Dakota that it was going to categorize warrantless breath tests as a search incident to arrest. The court finds this permissible under the Fourth Amendment as "[t]he impact of breath tests on privacy is slight, and the need for BAC testing is great." Just like it sounds, a search incident to arrest is a search conducted after a person is placed under arrest. The court articulated the general rule for these types of searches in Chimera v. California, stating "that arresting officers, in order to prevent the arrestee from obtaining a weapon or destroying evidence, could search both "the person arrested" and "the area ‘within his immediate control.'" The court stated this is a "categorical rule" meaning that the permissiblity of the search is not evaluated on a case by case, but rather "the mere 'fact of the lawful arrest' justifies 'a full search of the person.'" A warrant is not required for searches incident to arrest.

However, the court does not come to the same conclusion for blood tests. It stated that "[b]lood tests are significantly more intrusive, and their reasonableness must be judged in light of the availa­bility of the less invasive alternative of a breath test." Because it is much more intrusive, the court held that blood tests cannot be treated as searches incident to arrest and a warrant will likely needed for a blood draw.

In addressing if criminal sanctions are permissible in cases where a person refuses to take a chemical test, the court finds that it is appropriate to impose criminal penalties. Administrative penalties were imposed as an incentive to cooperate but states had begun imposing criminal penalties because the administrative penalties were "insufficient" to deter drivers, especially those who are repeat DUI offenders or those who had a significantly high BAC. Because the laws imposing criminal sanctions for refusal are meant to get people to cooperate with BAC testing, the court concluded that "they serve a very important function."

The court also looked at whether or not the implied consent law of a state is sufficient justification for a blood draw without a warrant. The court determines it is not enough, stating that drivers can be "deemed to have consented to only those conditions that are 'reasonable' in that they have a 'nexus' to the privilege of driving and entail penal­ties that are proportional to severity of the violation." Using this reasoning, the court stated that "motorists cannot be deemed to have consented to submit to a blood test on pain of committing a criminal offense."

The ruling is then applied to the three cases at hand:

• In Birchfield, the defendant refused to take a blood test without a warrant and was charged with a criminal offense because of his refusal. The court reversed his conviction and remanded it back to the lower courts.

• In Bernard, the defendant refused a breath test. As the court has decided that breath tests can be considered searches incident to arrest and are thus permissible without a warrant under the Fourth Amendment, Bernard's conviction is upheld.

• In Beylund, the defendant submitted to a blood test because he was told he could suffer additional criminal consequences if he did not. As Beylund was not given accurate information in light of the court's new ruling, the court vacated the judgment of the North Dakota Supreme Court and remanded the case back to the North Dakota courts so they could determine if Beylund's consent could be considered voluntary considering he was given incorrect information.

Justices Sotomayor and Ginsberg concurred in part and dissented in part.

Justice Thomas also concurred with part and dissented in part in a separate opinion from Justices Sotomayor and Ginsberg.