Investigatory stops must be based on what type of information?

Investigatory stops, also known as Terry stops, must be based on specific and articulable facts that would lead a reasonable officer to suspect that a person is involved in criminal activity. This requirement is grounded in the Fourth Amendment, which protects against unreasonable searches and seizures. The standard of "specific and articulable facts" means that officers must have a clear basis for their suspicions that is more than just a hunch or vague generalizations.

This ensures that the police action is justified and not arbitrary, protecting individual rights while allowing law enforcement to perform their duties effectively. The facts referred to can originate from the officer's observations, the behavior of the individual, or information from reliable sources, as long as it can be articulated clearly and specifically. Therefore, the requirement for specific and articulable facts is a fundamental principle in ensuring lawful investigatory stops.