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December 11, 2014 Articles

Traffic Stops Based on Mistake of Law: Are They Constitutional?

In Heien v. North Carolina, the Supreme Court could vastly expand police officers' discretion.

By LaKeisha R. Randall

You’ve heard the age-old adage: Ignorance of the law is no excuse. The law imputes knowledge of all laws to all persons within its jurisdiction, and they are equally susceptible to criminal punishment and civil liability. Seems fair, right? Well, what if a police officer misinterprets the law—should the officer be able to reasonably rely on that interpretation to justify a traffic stop or arrest?

In Heien v. North Carolina, No. 13-604, the first oral argument of the term, the U.S. Supreme Court considered “whether a police officer’s mistake of law can provide the individualized suspicion that the Fourth Amendment requires to justify a traffic stop.”

Facts of the Case 
On April 29, 2009, Sergeant Darisse of the Surry County Sheriff’s Department stopped Nicholas Heien and Maynor Javier Vasquez for having a broken right rear brake light. Vasquez was driving the petitioner’s car while Heien slept in the back seat. Suspicious of Heien lying under a blanket and Vasquez’s nervous behavior, Darisse asked for permission to search the vehicle and Heien consented. The officer found 54.2 grams of cocaine, and Heien was later indicted for two counts of drug trafficking.

Here’s the twist: Under North Carolina law, motor vehicles are required only to have “a stop lamp.” At trial, Heien argued that the North Carolina traffic law did not prohibit driving with one broken brake light so long as the other brake light was working.

He filed a motion to suppress the evidence discovered during the search of his vehicle and argued that the traffic stop violated the Fourth Amendment because Officer Darisse lacked “reasonable articulable suspicion that criminal activity had been committed or was being committed, or that a motor vehicle traffic offense or infraction had occurred.” He further contended that his subsequent consent to the search was invalid as fruit of the poisonous tree.

The trial court denied Heien’s motion, but the North Carolina Court of Appeals agreed and reversed, holding that the traffic stop was unconstitutional.

The court explained that, at the time of the stop, there was no violation of North Carolina law. “Because the initial stop was based upon Sergeant Darisse’s observation that the right brake light of the vehicle malfunctioned, the justification for the stop was objectively unreasonable, and the stop violated [d]efendant’s Fourth Amendment rights.” Essentially, the court held that a police officer’s mistaken belief about the requirements of the substantive traffic law is per se objectively unreasonable. And, when the factual circumstances fail to indicate a violation of the substantive law as interpreted by a reviewing court, the stop of an individual is unconstitutional.

In December 2012, the North Carolina Supreme Court overturned the appellate court’s ruling. North Carolina v. Heien, No. 380PA11 (Dec. 14, 2012). The Supreme Court of North Carolina used the “totality of the circumstances test” to determine the objective reasonableness of the officer’s mistake of law. Reasonableness, under this test, depends on the totality of the circumstances viewed by an objectively reasonable officer; as long as the surrounding context provides a particularized and articulable basis for suspecting criminal activity, reasonable suspicion exists.

An officer may make a mistake, including a mistake of law, yet still act reasonably under the circumstances. As stated above, when an officer acts reasonably under the circumstances, he is not violating the Fourth Amendment. So long as the officer’s mistake of law is objectively reasonable, then, the Fourth Amendment would seem not to be violated. Accordingly, requiring an officer to be more than reasonable, mandating that he be perfect, would impose a greater burden than that required under the Fourth Amendment.

North Carolina v. Heien, No. 380PA11, slip op. at 13–14.

The U.S. Supreme Court granted certiorari and has now considered whether a police officer’s mistake of law can serve as the requisite reasonable suspicion needed for a constitutional traffic stop.

Argument of the Parties
During oral argument, Heien primarily argued that reasonable suspicion must be measured against the correct interpretation of the law.

In a country dedicated to the rule of law, governmental officers should be presumed to know the law at least as well as the citizens are. That being so, when questions about individualized suspicion arise under the Fourth Amendment, they should be addressed against the backdrop of the correct interpretation of the law, not simply any plausible reading an officer might have.

Transcript of Oral Argument at 3, Heien v. North Carolina, No. 13-604 (argued Oct. 6, 2014).

The American Civil Liberties Union’s amicus brief, submitted with the National Association of Criminal Defense Lawyers and the Cato Institute, supported the petitioner and emphasized two principal flaws in the North Carolina Supreme Court’s approach: (1) It contradicts basic Fourth Amendment principles, improperly equating mistakes of fact with mistakes of law; and (2) if affirmed, it will have substantial negative consequences for both private citizens and law enforcement.

“Was the suspected act a crime? The legal rule—the ‘infraction itself,’ Whren v. United States, 517 U.S. 806, 818 (1996)—is the indispensable objective basis against which law enforcement, and courts, must evaluate observed facts.” Brief for the National Association of Criminal Defense Lawyers et al. at 4. Moreover, conflating mistakes of fact and law threatens the basic framework between citizens (who are presumed to know the law) and law enforcement officials (who, under the North Carolina Supreme Court’s approach, are not).

In response, the North Carolina Attorney General’s Office argued that the Fourth Amendment does not demand legal precision, only reasonableness.

The Fourth Amendment prohibits unreasonable searches and seizures, but it does not require that police officers be perfect. Because the touchstone of the Fourth Amendment is reasonableness, all that is required is that a police officer have a reasonable view of the facts and apply those facts to a reasonable understanding of the law.

Transcript of Oral Argument at 29.

Further, consider some of the statements made in the amicus brief filed on behalf of the Association of Prosecuting Attorneys in support of the state.

The reasonableness standard seeks to balance citizens’ privacy interests against providing law enforcement with enough leeway to effectively protect the community it serves. . . . Nothing suggests that allowing mistakes of law (as long as they are objectively reasonable) would upset this balance by encouraging excessive searches or seizures. On the other hand, imposing a standard of legal perfection would unduly complicate officers’ application of the Fourth Amendment in the field, lead to potentially harmful delay in their response to dangerous or criminal behavior, and meaninglessly thwart prosecution of crimes discovered during the stop.

Brief for the Association of Prosecuting Attorneys at 4.

Final Thoughts
Heien v. North Carolina presents a fundamental question about what we expect of our police force, and the outcome of this case could have grave implications. In a climate of Ferguson unrest, the government’s position would vastly expand police officers’ discretion. And, as the petitioner eloquently explained, this would allow officers to “stop cars and people whenever a ‘reasonable’ ambiguity of legal authority could be argued—creating broad authority and a double standard for ignorance of the law.”

A decision is expected by early in 2015.

Keywords: criminal litigation, Fourth Amendment, reasonable suspicion, ignorance of law, traffic stops

LaKeisha R. Randall is social action chair of the Criminal Litigation Committee and senior judicial law clerk in Atlanta, Georgia.

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