Fourth Amendment Protections: The Fourth Amendment in the U.S. Constitution safeguards individuals against unreasonable searches and seizures. In general, a seizure of a person is unreasonable under the Fourth Amendment if a police officer uses excessive force in making a lawful arrest.Generally, anyone acting under color of law—such as law enforcement officers—is not permitted to use force that is disproportionate to the situation. The Fourth Amendment to the United States Constitution prohibits the use of excessive force in the course of an arrest, investigatory stop, or other seizure. The Fourth Amendment of the U.S. Constitution guarantees a clearly established right to be free from excessive force at the hands of the police. 145. Al- though the Supreme Court has never invoked Graham v. Under the Fourth Amendment, a police officer may only use such force as is objectively reasonable under all of the circumstances.