How is policing effected by the 4th Amendment?

Answer 1

The 4th Amendment protects against unreasonable searches and seizures. All search warrants must be grounded in probable cause. All search warrants must be presented to an unbiased judge or magistrate to be approved and signed. So the 4th amendment affects policing by placing procedures/obstacles in path of police before they can conduct search. Issues can arise, however, as to what constitutes a search or seizure. There are, however, exemptions to when a search warrant is required.
Exceptions include search incident to lawful arrest, hot pursuit, exigent circumstances, and mobile objects, and grabbing area. Individuals can also "consent" to a search or seizure, and at this point, a search warrant is Not required.
There are also exceptions for airports, some checkpoints, and something called a "Terry" stop. A "Terry" stop occurs when a police officer has reasonable suspicion that crime is immediately afoot. At that point, the officer can conduct a pat-down, and if his concerns are not assuaged, he may conduct a full search.

Answer 2

The fourth admendment makes police officers get a search warrant before they can search your property. No search warrant shall be issued without probable cause.