Case Law Guide

In Millen v. Tennessee, the court applied the “transferred intent” rule. This means if someone tries to kill a specific person but accidentally kills someone else instead, the law treats it as if the intended target had been killed. In other words, the intent to harm the original target transfers to the unintended victim, making the defendant guilty of the same crime they would have committed if they had killed the intended person.

In simple terms: If you try to harm one person but accidentally hurt someone else, you're still responsible as if you'd hurt your original target.

In Dunaway v. New York, the U.S. Supreme Court ruled that when a person is seized without probable cause and transported to a police station for questioning, it violates the Fourth Amendment’s protection against unreasonable seizures and the Fourteenth Amendment’s due process protections. The Court held that such actions are not permissible even if the police intend to conduct an investigation rather than a formal arrest.

In simple terms: Police can’t detain and take someone to the station for questioning unless they have probable cause to arrest them.

In Rodriguez v. United States, the U.S. Supreme Court ruled that once a lawful traffic stop is completed, extending the stop to use a K-9 unit for a drug search violates the Fourth Amendment. The Court found that the additional time taken after the stop was completed was unreasonable and unnecessary, making the search illegal.

In simple terms: Police can’t hold someone longer than needed after a traffic stop just to use a K-9 unit for a search.

In United States v. Robinson, the U.S. Supreme Court decided that when an officer has probable cause to arrest a suspect—even for a minor offense like a traffic violation—they are allowed to perform a full search of the suspect, not just a limited pat-down for weapons. This search is justified as part of the arrest procedure and is meant to ensure officer safety and preserve evidence.

In simple terms: If someone is lawfully arrested, police can fully search them, even if the arrest was for something minor.

In United States v. Banks, the U.S. Supreme Court ruled that a 15 to 20-second wait before police forcibly entered a home was reasonable when investigating drug charges. The Court agreed that this brief delay was justified because any longer wait could risk evidence being destroyed, making it urgent for police to act swiftly.

In simple terms: Police don’t have to wait long to enter a home when investigating drugs if waiting any longer could lead to the destruction of evidence.

In Florida v. Royer, the U.S. Supreme Court ruled that when law enforcement officers take and hold a subject’s ID or driver’s license during a stop, the individual is considered “seized” under the Fourth Amendment. The Court also held that a person who is being illegally detained cannot give voluntary consent for a search of their belongings.

In Graham v. Connor, the Court established that when assessing whether excessive force was used, four factors must be considered: the severity of the crime, the immediate threat to officers or others, whether the suspect is resisting arrest, and whether the suspect is attempting to flee. The use of force must be reasonable from the perspective of an officer with similar training and experience.

In United States v. Sowards, the Court ruled that law enforcement officers are allowed to stop a vehicle for a visual estimation of speed, even if no radar or pacing was used, as long as there is a specific, objective reason to believe a traffic violation occurred.

In Scott v. Harris, the Court ruled that a police officer’s decision to end a dangerous high-speed chase by using force does not violate the Fourth Amendment, even if it results in injury or death to the fleeing driver, as long as the threat to public safety justifies the use of force.

In United States v. Arvizu, the U.S. Supreme Court ruled that law enforcement officers can stop a person based on reasonable suspicion, as long as it’s supported by the totality of the circumstances. This means that officers can consider all the facts and make inferences to determine if a stop is warranted, rather than relying on one single factor.

In simple terms: Police can stop someone if they have reasonable suspicion based on all the facts, not just one thing.

In Illinois v. Wardlow, the Court found that a person’s sudden, unprovoked flight from police in a high-crime area is sufficient to justify a stop based on reasonable suspicion. The Court also held that evasive behavior can contribute to establishing reasonable suspicion.

In United States v. Roe, the Court ruled that a suspect does not need to be inside their vehicle at the time of arrest for the vehicle to be searched. As long as the suspect has possession of the vehicle at the arrest scene, the entire passenger compartment can be searched.

In Chimel v. California, the Court decided that police officers may not search an entire home without a warrant during an arrest. However, they may search the area within the immediate reach of the person being arrested without a warrant.

In United States v. Ross, the Court held that law enforcement officers who have probable cause to believe a vehicle contains contraband may search the entire vehicle, including any containers within it, without a warrant.

In Canton v. Harris, the Court held that a municipality could be held liable for constitutional violations if it fails to properly train its officers, which leads to a failure in preventing constitutional violations by the officers.

In California v. Beheler, the Court clarified that Miranda warnings are not necessary if an individual is not in custody or significantly deprived of their freedom during questioning.

In Brinegar v. United States, the Court applied the "reasonableness test" for warrantless searches, stating that while police do not need to be factually correct, their actions must be reasonable under the circumstances.

In Arizona v. Grant, the Court ruled that police may only search the passenger compartment of a vehicle incident to a recent occupant’s arrest if it is reasonable to believe the arrestee might access the vehicle or if it contains evidence of the offense they were arrested for.

In Berkemer v. McCarty, the Court ruled that Miranda warnings are not required during routine questioning at a traffic stop. However, Miranda must be read when someone is subjected to custodial interrogation.

In Navarette v. California, the Court decided that officers can rely on an anonymous tip to establish reasonable suspicion, as long as there is reason to believe the tip is reliable, allowing for a stop and investigation.

In Carroll v. United States, the Court ruled that officers may search a vehicle without a warrant if they have probable cause to believe it contains contraband. This exception exists due to the mobility of vehicles and the impracticality of obtaining a warrant quickly.

In Terry v. Ohio, the Court ruled that police officers can stop and frisk individuals they reasonably suspect to be involved in criminal activity, even without probable cause, as long as there is reasonable suspicion.

In Tennessee v. Garner, the Court ruled that law enforcement officers may not use deadly force to stop a fleeing suspect unless there is probable cause to believe the suspect poses a significant threat of harm to others or the officer.

In Wyoming v. Houghton, the Court ruled that if officers have probable cause to search a vehicle for contraband, they can search the entire vehicle, including passengers' belongings, without a warrant or consent.

In Rollings v. Kentucky, the Court held that officers can search a person incident to arrest, even if the subject is not formally arrested at the time of the search.

In Arizona v. Johnson, the Court ruled that officers cannot search the driver or passengers of a vehicle unless there is reasonable suspicion that they are involved in criminal activity.

In Peyton v. New York, the Court ruled that police do not need a search warrant to enter a home if there is an arrest warrant for the person believed to be inside.

In Steagald v. United States, the Court ruled that officers cannot search a third-party's home, even if they have an arrest warrant for the suspect, unless they obtain a search warrant or have consent.

In Brendlin v. California, the Court ruled that a traffic stop applies to both the driver and passengers, and passengers are not free to leave until the officer decides to release them.

In United States v. Landeros, the Court ruled that officers cannot demand identification or arrest a passenger simply for not identifying themselves during a traffic stop, as it does not provide probable cause.

In Michigan v. Summers, the Court ruled that officers may detain a person present at the location of a valid search warrant execution to ensure officer safety during the search.

In Delaware v. Prouse, the Court ruled that officers cannot stop a vehicle without probable cause or reasonable suspicion. The stop must be justified with solid evidence of a violation.

In United States v. Ross, the Court ruled that officers may search a vehicle without a warrant if they have probable cause to believe it contains contraband, including any containers found inside.

In Berkemer v. McCarty, the Court ruled that routine questioning during a traffic stop does not require Miranda warnings, but Miranda is necessary when the individual is subjected to custodial interrogation.

In Pennsylvania v. Mimms, the Court ruled that during a lawful traffic stop, officers can order the driver and passengers to exit the vehicle without additional justification due to safety concerns.

In United States v. Sharpe, the Court ruled that the duration of a traffic stop does not violate constitutional rights as long as officers act diligently and the stop is not excessively prolonged.

In Arkansas v. Sullivan, the Court ruled that officers may stop a vehicle based on reasonable suspicion of an impending crime, even if it is just a hunch, to investigate further.

In Kansas v. Glover, the U.S. Supreme Court decided that if a police officer knows the owner of a car has a revoked driver's license, the officer can reasonably assume the owner is the one driving the car—unless there’s evidence to suggest otherwise. Based on this assumption, the officer is allowed to stop the car briefly to investigate, as this doesn’t violate the Fourth Amendment’s protection against unreasonable searches and seizures.

In simple terms: If the car owner isn’t supposed to drive and no other information suggests someone else is driving, the officer can stop the car to check.

In Texas v. Brown, the Court ruled that an object is in "plain view" if it can be seen without violating a person's privacy, and abandoned items can be searched without a warrant or consent.

In Michigan v. Long, the Court extended Terry v. Ohio to allow officers to search a vehicle during a stop if they believe the suspect may be dangerous and could reach for a weapon.