The 9.23 Particular Rights-Fourth Amendment-Unreasonable Seizure of Person-Probable Cause Arrest is a type of arrest that requires the police to have probable cause to believe that a person has committed a crime before they can lawfully arrest them. Probable cause is defined as having enough facts or evidence to believe that a crime was committed. This type of arrest is based on the Fourth Amendment of the United States Constitution, which protects citizens from unreasonable searches and seizures. There are two types of 9.23 Particular Rights-Fourth Amendment-Unreasonable Seizure of Person-Probable Cause Arrest: warrant-based and warrantless. Warrant-based arrests require police to get a warrant from a judge before arresting someone, while warrantless arrests allow police to make an arrest without a warrant but still require probable cause.