What is the standard definition of probable cause?

The standard definition of probable cause is articulated as a reasonable belief that evidence of a crime will be found. This definition is grounded in the Fourth Amendment, which protects individuals from unreasonable searches and seizures. Probable cause requires a level of certainty based on factual circumstances that would lead a reasonable person to believe that a crime has been committed, or that evidence related to a crime is present in a particular location.

This standard is more rigorous than mere suspicion or hunches; it demands facts or circumstances that would lead a prudent person to conclude that a search or arrest is justified. It is not solely based on the subjective beliefs or opinions of officers but must be rooted in observable facts or reliable information.

While suspicion of criminal activity may motivate an investigation, it does not rise to the level of probable cause. Similarly, a hunch, which lacks concrete evidence, cannot form the basis for probable cause, and relying on the opinions of officers is also insufficient without a foundation of facts that affirmatively support a reasonable belief in the existence of evidence related to a crime.