Case Citation
Legal Case Name

AGUILAR v. TEXAS Case Brief

Supreme Court of United States1964
378 U.S. 108 84 S.Ct. 1509 12 L.Ed.2d 723 Criminal Procedure Constitutional Law Evidence

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Case Brief Summary & Legal Analysis

General Brief
3 min read

tl;dr: Police obtained a search warrant based on an affidavit claiming a “credible” informant’s tip. The Supreme Court found the affidavit insufficient because it lacked facts about the informant’s reliability or the basis of their knowledge, rendering the warrant invalid under the Fourth Amendment.

Legal Significance: This case established the influential “Aguilar-Spinelli test,” a two-pronged standard for evaluating probable cause based on informants’ tips. The affidavit must demonstrate the informant’s basis of knowledge and provide facts supporting their credibility or the reliability of their information.

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Case Facts & Court Holding

Key Facts & Case Background

Two Houston police officers applied for a warrant to search petitioner Aguilar’s home for narcotics. The supporting affidavit stated that the officers had “received reliable information from a credible person and do believe” that Aguilar possessed heroin and other narcotics for sale at his residence. The affidavit did not provide any underlying facts to support these assertions. It failed to explain how the informant obtained the information (e.g., through personal observation) or provide any basis for the officers’ conclusion that the informant was credible (e.g., a history of providing accurate tips). A local Justice of the Peace issued a search warrant based solely on this affidavit. The subsequent search of Aguilar’s home uncovered heroin, which was introduced as evidence at his trial. Over his Fourth Amendment objection, Aguilar was convicted of illegal possession of heroin in Texas state court.

Court Holding & Legal Precedent

Issue: Does a search warrant affidavit that relies on an informant’s tip satisfy the Fourth Amendment’s probable cause requirement if it fails to provide the magistrate with the underlying circumstances from which the officer concluded the informant was credible and from which the informant concluded the narcotics were present?

No. The Court held that the affidavit was insufficient to establish probable Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commod

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Legal Issue

Does a search warrant affidavit that relies on an informant’s tip satisfy the Fourth Amendment’s probable cause requirement if it fails to provide the magistrate with the underlying circumstances from which the officer concluded the informant was credible and from which the informant concluded the narcotics were present?

Conclusion

Aguilar established a rigorous, two-part framework for assessing probable cause based on Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in vo

Legal Rule

For a search warrant affidavit based on an informant's hearsay to be Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt i

Legal Analysis

The Supreme Court, applying the Fourth Amendment to the states through the Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaeca

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  • An affidavit for a search warrant based on an informant’s tip
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in volu

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