The Good-Faith Exception to Law Enforcement Search and Seizure Rules

The Fourth Amendment protection against unreasonable searches and seizures usually allows a defendant to exclude evidence from a trial if it was unconstitutionally seized. However, there are several exceptions to search and seizure rules. One of these involves evidence that law enforcement seizes in good faith. If the police make a reasonable mistake in conducting a search, evidence of a crime that they find as a result may be admissible. The U.S. Supreme Court has ruled that a court can consider evidence obtained from a search that appeared to have a lawful basis, such as a search supported by a warrant. If the warrant later turns out to have been invalid, the police may not be held accountable for conducting a search while relying on it.

Meeting the Requirements for the Exception

The good-faith exception does not apply when an improper act occurs at any point during the search, including the process of obtaining a search warrant.

To trigger the exception, the police need to behave properly throughout the search. They cannot engage in other misconduct or make obvious mistakes during the process that a reasonable, well-trained officer would not make. For example, a reasonable police officer should be able to determine when a warrant is too vague and will be considered invalid. If they still conduct a search and seizure based on that warrant, the good-faith exception will not cover evidence that they obtain. A defendant can file a motion to suppress that evidence.

Also, if an officer gets a warrant through their own misconduct, this will not trigger the good-faith exception. An officer cannot invent or exaggerate facts to convince a judge to issue a warrant and then claim the exception for evidence seized while executing the warrant. This is also true if one officer makes the misleading application for the warrant, and another officer reasonably relies on the warrant in carrying out the search.

Some situations in which the good-faith exception usually applies are when police agencies make mistakes in maintaining warrant databases, which can result in confusion over the names of suspects. A mistake of law by a police officer sometimes can trigger the exception. If an officer takes steps based on the existing interpretation of the law, but a court later rules that the law should be interpreted differently, they may be found to have acted in good faith. Evidence acquired because of this mistake may be admitted at a trial.

Why Have the Exception?

United States v. Leon

The good-faith exception originated in United States v. Leon (1984).

The reason for a defendant’s right to suppress evidence obtained through an unconstitutional search is to prevent law enforcement from engaging in misconduct. Thus, when law enforcement takes reasonable steps, suppressing the resulting evidence does not serve the purpose of the Fourth Amendment. Debates have arisen over whether this reasoning is valid. Some legal scholars believe that criminal defendants should not pay the price for mistakes by the police, even if there were no bad intentions. It is also often hard to draw the line between innocent mistakes and mistakes that seem innocent but may be intended to dodge constitutional rules.

Due to the controversy surrounding the good-faith exception, some states do not apply it in their courts. Other states apply a limited version of it. This is because states have a right to provide greater liberties to their citizens under their own constitutions than those contained in the U.S. Constitution. If you think that the good-faith exception might arise in your case, you should consult an attorney to discuss its scope in your state.

Last reviewed October 2023

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