ABSTRACT
“Probable cause” is the most important and most often used phrase in law enforcement. It is defined by the United States Supreme Court as more than bare suspicion; it exists when “the facts and circumstances within the officers’ knowledge and of which they had reasonably trustworthy information are sufficient in themselves to warrant a man of reasonable caution in the belief that an offense has been or is being committed.” The leading cases briefed in this chapter on probable cause are Draper v. United States and Illinois v. Gates.
