Apparent facts discovered through logical inquiry that would lead a reasonably intelligent and prudent person to believe that an accused person has committed a crime, thereby warranting his or her prosecution, or that a CAUSE OF ACTION has accrued, justifying a civil lawsuit.
Probable cause is a level of reasonable belief, based on facts that can be articulated, that is required to sue a person in civil court or to arrest and prosecute a person in criminal court. Before a person can be sued or arrested and prosecuted, the civil plaintiff or police and prosecutor must possess enough facts that would lead a reasonable person to believe that the claim or charge is true.
The probable cause standard is more important in CRIMINAL LAW than it is in CIVIL LAW because it is used in criminal law as a basis for searching and arresting persons and depriving them of their liberty. Civil cases can deprive a person of property, but they cannot deprive a person of liberty. In civil court a plaintiff must possess probable cause to levy a claim against a defendant. If the plaintiff does not have probable cause for the claim, she may later face a MALICIOUS PROSECUTION suit brought by the defendant. Furthermore, lack of probable cause to support a claim means that the plaintiff does not have sufficient evidence to support the claim, and the court will likely dismiss it.
In the criminal arena probable cause is important in two respects. First, police must possess probable cause before they may search a person or a person's property, and they must possess it before they may arrest a person. Second, in most criminal cases the court must find that probable cause exists to believe that the defendant committed the crime before the defendant may be prosecuted.
There are some exceptions to these general rules. Police may briefly detain and conduct a limited search of a person in a public place if they have a reasonable suspicion that the person has committed a crime. Reasonable suspicion is a level of belief that is less than probable cause. A police officer possesses reasonable suspicion if he has enough knowledge to lead a reasonably cautious person to believe that criminal activity is occurring and that the individual played some part in it. In practice this requirement means that an officer need not possess the measure of knowledge that constitutes probable cause to STOP AND FRISK a person in a public place. In...