Answer :
Probable cause is a legal standard for issuing warrants or making warrantless arrests under exigent circumstances, while reasonable suspicion is a lower standard allowing for brief stops and frisks, such as those in Terry v. Ohio. Both are foundational for police search and seizure operations under the Fourth Amendment protections against unreasonable searches and seizures.
The concepts of probable cause and reasonable suspicion are legal standards applied under different circumstances. Probable cause is a legal standard used to determine the constitutionality of a search or seizure and is required for obtaining search warrants or making arrests without a warrant, when exigent circumstances apply. It indicates that there is a fair probability that a crime has been committed or that evidence of a crime will be found.
On the other side, reasonable suspicion is a lower standard than probable cause and applies to less intrusive police encounters, such as stopping and frisking individuals on the street, as established in the landmark case Terry v. Ohio (1968). Here, police can conduct a brief 'stop and frisk' based on a reasonable suspicion that the person has, is, or is about to commit a crime.
These standards are both crucial in balancing law enforcement objectives with individuals' rights protected under the Fourth Amendment, which prohibits unreasonable searches and seizures. In some situations, such as when searching a vehicle during a traffic stop, police may only need probable cause to believe that contraband is present to search without a warrant.
