Fourth Amendment Searches Can Be Based on Reasonable Mistakes of Law

The U.S. Supreme Court issued an opinion in Heien v. North Carolina, which asked the Court to consider whether a mistake of law justifies a traffic stop and subsequent Fourth Amendment search and seizure. The Court held that it does, but only if the legal error is objectively reasonable.

The Facts of Heien

A North Carolina police officer stopped Heien for driving with a broken brake light. The officer asked Heien for permission to search the vehicle, and Heien agreed. The officer then discovered cocaine hidden in a duffle bag in the car, which led to Heien’s conviction for attempted drug trafficking. On appeal, the North Carolina appellate court found that state law only requires one working brake light. Thus, the court held that Heien did not violate the law by driving with one broken brake light, and that the officer’s mistake of law did not permit the stop.

The North Carolina Supreme Court reversed the lower court’s decision, ruling that the officer’s mistake was reasonable and therefore did not violate the Fourth Amendment guarantee against “unreasonable” searches and seizures. Heien appealed to the U.S. Supreme Court, which upheld the North Carolina court’s decision.

Reasonable Mistakes of Law

The U.S. Supreme Court’s 8-1 ruling that a reasonable mistake of law justifies a Fourth Amendment search is in line with its prior ruling that a constitutional search may be based on a reasonable mistake of fact. However, the Court stressed the mistake of law reasonableness standard is not very “forgiving.” An officer cannot justify a legal error made on his own subjective understanding of the law. Rather, the mistake must be objectively reasonable. In other words, the statute must be “genuinely ambiguous” and difficult to interpret.

The lone dissenter, Justice Sonia Sotomayor, argued that a “fixed legal yardstick” would be preferable to the Court’s “reasonable” mistake of law standard.

A Private Citizen’s Mistake of Law

It is important to distinguish between a police officer’s mistake of law and a private citizen’s mistake of law. Generally, ignorance is not a valid defense for criminal offenders. If you have been charged with a crime, you will not be acquitted by claiming that you did not know your actions were criminal (although there are very limited exceptions to this rule; see Lambert v. California). Similarly, if a police officer breaks the law, he may not use ignorance of the law to excuse his criminal actions. The difference lies in upholding the law versus breaking the law. Heien allows police officers to perform Fourth Amendment searches and seizures based on their objectively reasonable mistakes of law.

Contact Us Today

Contact our Will County criminal defense attorneys today if your constitutional rights have been violated during the course of a traffic stop or during any search and seizure. We can assist those in Frankfort, Joliet and the surrounding area.

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