The exception to the requirement of a warrant for automobiles does not require a separate finding of exigency, in addition to a finding of probable cause. Maryland v. Dyson, 527 U.S. 465, 119 S. Ct. 2013, 144 L. Ed. 2d 442 (1999). When there is probable cause to search a motor vehicle, the search is not unreasonable if the search is based on facts that would justify the issuance of a warrant, although a warrant was not obtained. No separate finding of exigent circumstances is required. Maryland v. Dyson, 527 U.S. 465, 119 S. Ct. 2013, 144 L. Ed. 2d 442 (1999). An anonymous tip that a person is carrying a gun, without more, is insufficient to justify a police officer’s stop and frisk of a person. The tip must bear indicia of reliability. Reasonable suspicion requires that a tip be reliable in its assertion of criminal activity, not just in its tendency to identify a person. Florida v. J.L., 529 U.S. 266, 120 S. Ct. 1375, 146 L. Ed. 2d 254 (2000). Stopping vehicles at highway checkpoints without any individualized suspicion to interdict illegal drugs was an unreasonable seizure under the 4th amendment because the primary purpose was to uncover evidence of ordinary criminal wrongdoing, unlike checkpoints to check for drunk driving or illegal immigrants. City of Indianapolis v. Edmond, 531 U.S. 32, 121 S. Ct. 447, 148 L. Ed. 2d 333 (2000). The police acted reasonably when, with probable cause to believe that the defendant had hidden drugs in his home, they prevented the man from entering the home for about two hours until a search warrant could be obtained. Illinois v. McArthur, 531 U.S. 326, 121 S. Ct. 946, 148 L. Ed. 2d 838 (2001). A state hospital could not test maternity patients for cocaine and then turn the results over to law enforcement authorities without patient consent. The interest of using the threat of criminal sanctions to deter pregnant women from using cocaine does not justify a departure from the rule that a nonconsensual search is unconstitutional if not authorized by a warrant. Ferguson v. City of Charleston, 532 U.S. 67, 121 S. Ct. 1281, 149 L. Ed. 2d 205 (2001). If an officer has probable cause to believe a person has committed even a very minor criminal offense that does not breach the peace, the officer may, without violating the 4th amendment, arrest the offender without the need to balance the circumstances involved in the particular situation. Atwater v. City of Lago Vista, 532 U.S. 318, 121 S. Ct. 1536, 149 L. Ed. 2d 549 (2001). Obtaining, by sense-enhancing technology like infrared imaging, information regarding the interior of a home that could otherwise not be obtained without physical intrusion into a constitutionally protected area is a search presumptively unreasonable without a warrant. Kyllo v. United States, 533 U.S. 27, 121 S. Ct. 2038, 150 L. Ed. 2d 94 (2001). A warrantless search of a probationer’s residence founded on reasonable suspicion of criminal activity and authorized as a condition of probation was reasonable. Such a search is not restricted to monitoring whether the probationer is complying with probation restrictions. United States v. Knights, 534 U.S. 112, 122 S. Ct. 587, 151 L. Ed. 2d 497 (2001). Police officers may approach bus riders at random to ask questions and to request consent to search luggage without advising the passengers of their right to not cooperate. United States v. Drayton, 536 U.S. 194, 122 S. Ct. 2105, 153 L. Ed. 2d 242 (2002). A school district policy of requiring all participants in competitive extracurricular activities to submit to drug testing was a reasonable means of furthering the district’s interest in preventing drug use among students and was not an unreasonable search. Board of Education of Independent School District No. 92 v. Earls, 536 U.S. 822, 122 S. Ct. 2559, 153 L. Ed. 2d 735 (2002). A highway checkpoint where police stopped motorists to ask them for information about a recent hit-and-run was reasonable. The arrest of a drunk driver arrested when his vehicle swerved nearly hitting an officer at the checkpoint was constitutional. Illinois v. Lidster, 540 U.S. 419, 124 S. Ct. 885, 157 L. Ed. 2d 843 (2004). When a police officer has made a lawful custodial arrest of an occupant of an automobile, the 4th amendment allows the officer to search the passenger compartment of that vehicle as a contemporaneous incident of arrest whether the officer makes contact with the occupant while the occupant is inside the vehicle, or when the officer first makes contact with the arrestee after the latter has exited the vehicle. Thornton v. United States, 541 U.S. 615, 124 S. Ct. 2127, 158 L. Ed. 2d 905 (2004). The principles of Terry, 392 U.S. 1 (1968), permit a state to require a suspect to disclose his or her name in the course of a Terry stop and allow imposing criminal penalties for failing to do so. Hiibel v. Sixth Judicial District Court, 542 U.S. 177, 124 S. Ct. 2451, 159 L. Ed 2d 292 (2004). The 4th amendment does not require reasonable, articulable suspicion to justify using a drug-detection dog to sniff a vehicle during a legitimate traffic stop. The use of a well-trained narcotics-detection dog that does not expose noncontraband items that otherwise would remain hidden from public view during a lawful traffic stop, generally does not implicate legitimate privacy interests. Illinois v. Caballes, 543 U.S. 405, 125 S. Ct. 834, 160 L. Ed. 2d 842 (2004). Police may enter a home without a warrant when they have an objectively reasonable basis for believing that an occupant is seriously injured or imminently threatened with such injury. An action is reasonable under the 4th amendment, regardless of the individual officer’s state of mind, as long as the circumstances, viewed objectively, justify the action. Brigham City v. Stuart, 547 U.S. 398, 126 S. Ct. 1943, 164 L. Ed. 2d 650 (2006). Warrantless arrests for crimes committed in the presence of an arresting officer are reasonable under the U.S. Constitution, and while states are free to regulate such arrests however they desire, state restrictions do not alter the 4th amendment’s protections. Virginia v. Moore, 553 U.S. 164, 128 S. Ct. 1598, 170 L. Ed. 2d 559 (2008). In a traffic-stop setting, the first Terry, 392 U.S. 1 (1968), condition—a lawful investigatory stop—is met whenever it is lawful for police to detain an automobile and its occupants pending inquiry into a vehicular violation. The police need not have, in addition, cause to believe any occupant of the vehicle is involved in criminal activity. To justify a patdown of the driver or a passenger during a traffic stop, however, the police must harbor reasonable suspicion that the person subjected to the frisk is armed and dangerous. Arizona v. Johnson, 555 U.S. 323, 129 S. Ct. 781, 172 L. Ed. 2d 694 (2009). Belton, 453 U.S. 454 (1981), does not authorize a vehicle search incident to a recent occupant’s arrest after the arrestee has been secured and cannot access the interior of the vehicle. Police are authorized to search a vehicle incident to a recent occupant’s arrest only when the arrestee is unsecured and within reaching distance of the passenger compartment at the time of the search. Consistent with Thornton, 541 U.S. 615 (2004), circumstances unique to the automobile context justify a search incident to arrest when it is reasonable to believe that evidence of the offense of arrest might be found in the vehicle. Arizona v. Gant, 556 U.S. 332, 129 S. Ct. 1710, 173 L. Ed. 2d 485 (2009). The T.L.O., 469 U.S. 325 (1985), concern to limit a school search to a reasonable scope requires reasonable suspicion of danger or a resort to hiding evidence of wrongdoing in underwear before a searcher can reasonably make the quantum leap from a search of outer clothes and backpacks to exposure of intimate parts. The meaning of such a search, and the degradation its subject may reasonably feel, place a search that intrusive in a category of its own demanding its own specific suspicions. Safford Unified School District No. 1 v. Redding, 557 U.S. 364, 129 S. Ct. 2633, 174 L. Ed. 2d 354 (2009). A government employer had the right, under the circumstances of the case, to read text messages sent and received on a pager the employer owned and issued to an employee. The privacy of the messages was not protected by the ban on “unreasonable searches and seizures” found in the 4th amendment. Because the search was motivated by a legitimate work related purpose, and because it was not excessive in scope, the search was reasonable. Ontario v. Quon, 560 U.S. 746, 130 S. Ct. 2619, 177 L. Ed. 2d 216 (2010). Warrantless searches are allowed when the circumstances make it reasonable, within the meaning of the 4th amendment, to dispense with the warrant requirement. The exigent circumstances rule justifies a warrantless search when the conduct of the police preceding the exigency is reasonable in the same sense. When the police do not create the exigency by engaging or threatening to engage in conduct that violates the 4th amendment, warrantless entry to prevent the destruction of evidence is reasonable and thus allowed. Kentucky v. King, 563 U.S. 452, 131 S. Ct. 1849, 179 L. Ed. 2d 865 (2011). The government’s installation of a global-positioning-system (GPS) device on a target’s vehicle, and its use of that device to monitor the vehicle’s movements, constitutes a “search.” United States v. Jones, 565 U.S. 400, 132 S. Ct. 945, 181 L. Ed. 2d 911 (2012). Whether an official protected by qualified immunity may be held personally liable for an allegedly unlawful official action generally turns on the objective legal reasonableness of the action, assessed in light of the legal rules that were clearly established at the time the action was taken. When an alleged 4th amendment violation involves a search or seizure pursuant to a warrant, the fact that a neutral magistrate has issued a warrant is the clearest indication that the officers acted in an objectively reasonable manner. There is a narrow exception allowing suit when it is obvious that no reasonably competent officer would have concluded that a warrant should issue. Messerschmidt v. Millender, 565 U.S. 535, 132 S. Ct. 1235, 182 L. Ed. 2d 47 (2012). Generally, every detainee who will be admitted to the general jail population may be required to undergo a close visual inspection while undressed. Undoubted security imperatives involved in jail supervision override the assertion that some detainees must be exempt from these invasive procedures absent reasonable suspicion of a concealed weapon or other contraband. Deference must be given to the officials in charge of the jail unless there is substantial evidence demonstrating their response to the situation is exaggerated. Florence v. Board of Chosen Freeholders of County of Burlington, 566 U.S. 318, 132 S. Ct. 1510, 182 L. Ed. 2d 566 (2012). The categorical authority to detain incident to the execution of a search warrant must be limited to the immediate vicinity of the premises to be searched. A spatial constraint defined by the immediate vicinity of the premises to be searched is therefore required for detentions incident to the execution of a search warrant. Limiting the rule in Summers, 452 U.S. 692 (1981), to the area in which an occupant poses a real threat to the safe and efficient execution of a search warrant ensures that the scope of the detention incident to a search is confined to its underlying justification. Once an occupant is beyond the immediate vicinity of the premises to be searched, the search-related law enforcement interests are diminished and the intrusiveness of the detention is more severe. Bailey v. United States, 568 U.S. 186, 133 S. Ct. 1031, 185 L. Ed. 2d 19 (2013).