Chapter 6

Police and Law

Legal Limitations on Police Investigations

• Bill of Rights embodies American values regarding individual rights

  • Judges must interpret the Constitution to balance crime control and individual rights.

• Search and seizure concepts

  • Search: actions by police that intrude on a person’s reasonable expectation of privacy.

  • Seizure: use of authority to deprive someone of liberty or property

    • e.g., arrest

  • A stop is a brief interference with a person’s freedom that can be measured in minutes, and police must have reasonable suspicion to stop most of the time.

• Plain view doctrine: permits officers to notice and use as evidence visible items

Use of force and the Fourth Amendment

• Tennessee v. Garner (1985):

  • police may not use deadly force in apprehending fleeing felons unless they must to keep the suspect from escaping and the officer has probable cause that the suspect poses a significant threat of death or serious physical injury.

    • Determined from the officer’s perspective (Graham)

• To arrest a suspect and take them into custody, the police need probable cause, showing that sufficient evidence exists to make it likely the suspect committed the crime.

  • Warrants require probable cause, affirmation by affidavit (states what happened), particular description

  • Probable cause is determined by the totality of the circumstances.

Warrantless Searches

• Special needs beyond the normal purposes of law enforcement

  • Airport metal detectors, sobriety checkpoints

• Stop and frisk on the streets

  • Terry v. Ohio: officer may frisk a person briefly stopped

• Search incident to a lawful arrest

  • Chimel v. California: allows weapon search during arrest

• Marilyn v. Keen (spelling?)

  • DNA cheek swabs

• Exigent circumstances

  • Immediate threat to public safety or evidence

• Consent search

  • Automobile searches (inventory)

Questioning suspects

• Fifth Amendment privilege against compelled self-incrimination discourages police officers from using violent or coercive means to force a confession.

• Miranda v. Arizona (1966): Suspects being taken into custody must be told four things before they are questioned.

  • They have the right to remain silent.

  • Any statement can and will be used against them.

  • They have the right to an attorney.

  • If they cannot afford an attorney, the state will provide one.

• There is an exception for public safety.

• Most interrogations must be videotaped.

Exclusionary Rule

• Illegally obtained evidence must be excluded from trial

  • Weeks v. United States (1914): established rule in federal prosecutions

  • Wolf v. Colorado (1949): incorporated the Fourth Amendment

  • Mapp v. Ohio (1961): applied to states

• Exceptions

  • Good faith (United States v. Leon)

    • Officer believes they’re following the proper procedures

  • Inevitable discovery (Nix v. Williams)