1) Tennessee v. Garner, court held police can only use deadly force if the suspect is posing a significant threat of death or serious injury to others.
2) County of Riverside v. McLaughlin, ruled, “Where an arrested individual does not receive a probable cause determination within 48 hours, the burden of proof shifts to the government to demonstrate the existence of a bona fide emergency or other extraordinary circumstance, which cannot include intervening weekends or the fact that, in a particular case, it may take longer to consolidate pretrial proceedings.”
3) When there is commission of a felony
4) When there is probable Cause. It cannot be NEVER, since there are exemptions to the warrant requirement such as hot pursuit that exempt entry without a warrant.
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