What is Probable Cause?
In the United States criminal justice system, probable cause refers to the standard by which a police officer has the right to make an arrest, conduct a personal search or property search, or to obtain an arrest warrant. A police officer or other law enforcement official must have probable cause to arrest someone in a legal fashion.
Probable cause is also used to refer to the standard to which a grand jury believes that a crime has been committed. This term comes from the Fourth Amendment of the United States Constitution, which states the following:
The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.
Private detectives and police officers should clearly understand probable cause to ensure they are always operating within the guidelines of the law. In a court of law, evidence can be dismissed and entire cases can be dismissed based on whether cops had the appropriate authority to conduct a search or obtain a warrant to make an arrest.
For more legal definitions, visit our Glossary of Legal and Investigation Terms.