The particularity requirement under the 4th amendment provides that a warrant must enable the searcher to reasonably ascertain and identify the things that are authorized to be seized. While a description of the object into which a tracking device is to be placed is a factor in satisfying the particularity requirement in Sveum, 2010 WI 92, there is no reason why another way of identifying a cell phone, such as by its electronic serial number, cannot serve the same function as physically placing a tracking device on the defendant’s property. State v. Tate, 2014 WI 89, 357 Wis. 2d 172, 849 N.W.2d 798, 12-0336.

The 4th amendment parameters of search and seizure law are not necessarily inapplicable to all searches for and seizures of electronic information. Law enforcement officers have long had to separate the documents as to which seizure was authorized from other documents. That necessity has not turned an otherwise valid warrant into a “general” warrant. The court saw no constitutional imperative that would change the result simply because the object of the search is electronic data from a specific electronic file, for a reasonably specific period of time, in the custody of a specific internet service provider. State v. Rindfleisch, 2014 WI App 121, 359 Wis. 2d 147, 857 N.W.2d 456, 13-0362.

Police may properly consider prior convictions in a probable cause determination. State v. Blatterman, 2015 WI 46, 362 Wis. 2d 138, 864 N.W.2d 26, 13-2107.

Whether probable cause exists to issue a warrant is an objective, not a subjective, test. Thus, a police officer’s failure to tell the warrant-issuing court the officer’s subjective viewpoint was irrelevant and was not a “critical omission” from the affidavit supporting the search warrant so as to constitute a Franks, 438 U.S. 154 (1978), violation. State v. Kilgore, 2016 WI App 47, 370 Wis. 2d 198, 882 N.W.2d 493, 15-0997.

A tip from an electronic service provider (ESP) is properly viewed as one from an identified citizen informant, not an anonymous informant, which therefore establishes the personal reliability requirement in case law. Additionally, the affidavit in this case showed sufficient indicia of observational reliability of the ESP. State v. Silverstein, 2017 WI App 64, 378 Wis. 2d 42, 902 N.W.2d 550, 16-1464.

Suppression of evidence under the exclusionary rule is not appropriate when there is no police misconduct because the sole purpose of the exclusionary rule is to deter police misconduct. Neither judicial integrity nor judicial error is a standalone basis for suppression under the exclusionary rule. State v. Kerr, 2018 WI 87, 383 Wis. 2d 306, 913 N.W.2d 787, 16-2455.

A warrant for global positioning system (GPS) tracking is not issued pursuant to a statute, but instead is issued pursuant to the court’s inherent authority, and thus must comply only with this section and the 4th amendment to the U.S. Constitution. State v. Pinder, 2018 WI 106, 384 Wis. 2d 416, 919 N.W.2d 568, 17-0208.

The purpose of an oath or affirmation is to impress upon the swearing individual an appropriate sense of obligation to tell the truth. The constitutional guarantee that warrant applications be supported by oath or affirmation is satisfied when the facts and circumstances demonstrate that the affiant executes an affidavit in a form calculated to awaken the conscience and impress the mind with the duty to tell the truth. The constitution does not require that any specific language or procedure be employed in the administration of an oath or affirmation. The oath or affirmation requirement is an issue of substance, not form. State v. Moeser, 2022 WI 76, 405 Wis. 2d 1, 982 N.W.2d 45, 19-2184.

An anonymous telephone tip that specified that a vehicle was driven by an unlicensed person did not create articulable and reasonable suspicion of illegality justifying an investigatory stop of the auto and driver. 68 Atty. Gen. 347.

When a defendant makes a substantial preliminary showing that an affiant’s false statement, knowingly or recklessly made, was the basis of the probable cause finding, a hearing must be held. Franks v. Delaware, 438 U.S. 154, 98 S. Ct. 2674, 57 L. Ed. 2d 667 (1978).

An “open-ended” search warrant was unconstitutional. Lo-Ji Sales, Inc. v. New York, 442 U.S. 319, 99 S. Ct. 2319, 60 L. Ed. 2d 920 (1979).

The two-pronged test of Aguilar, 378 U.S. 108 (1964), and Spinelli, 393 U.S. 410 (1969), is abandoned and replaced with a “totality of the circumstances” approach in finding probable cause based on informer’s tips. Illinois v. Gates, 462 U.S. 213, 103 S. Ct. 2317, 76 L. Ed. 2d 527 (1983).

Under the totality of circumstances test, an informant’s tip met probable cause standards. Massachusetts v. Upton, 466 U.S. 727, 104 S. Ct. 2085, 80 L. Ed. 2d 721 (1984).

The good faith exception to the exclusionary rule allowed the admission of evidence obtained by officers acting in objectively reasonable reliance on a search warrant, issued by a detached and neutral magistrate, later found to be unsupported by probable cause. United States v. Leon, 468 U.S. 897, 104 S. Ct. 3405, 82 L. Ed. 2d 677 (1984).

Probable cause is required to invoke the plain view doctrine. Arizona v. Hicks, 480 U.S. 321, 107 S. Ct. 1149, 94 L. Ed. 2d 347 (1987).

Evidence seized in reliance on a police record incorrectly indicating an outstanding arrest warrant was not subject to suppression when the error was made by court clerk personnel. Arizona v. Evans, 514 U.S. 1, 115 S. Ct. 1185, 131 L. Ed. 2d 34 (1995).

There is no blanket exception to the knock and announce requirement for executing warrants. To justify a no-knock entry, a reasonable suspicion that knocking and announcing will be dangerous or futile or will inhibit the effective investigation of a crime must exist. Richards v. Wisconsin, 520 U.S. 385, 117 S. Ct. 1416, 137 L. Ed. 2d 615 (1997).

When the three occupants of a vehicle in which drugs and cash were found in a legal search all failed to offer any information with respect to the ownership of the drugs or money, it was a reasonable inference that any or all three of the occupants had knowledge of, and exercised dominion and control over, the drugs. A reasonable officer could conclude that there was probable cause to believe one or more of the occupants possessed the drugs, either solely or jointly. Maryland v. Pringle, 540 U.S. 366, 124 S. Ct. 795, 157 L. Ed. 2d 769 (2003).

A search warrant that did not describe the items to be seized at all was so obviously deficient that the search conducted pursuant to it was considered to be warrantless. Groh v. Ramirez, 540 U.S. 551, 124 S. Ct. 1284, 157 L. Ed. 2d 1068 (2004).

Whether probable cause exists depends upon the reasonable conclusion to be drawn from the facts known to the arresting officer at the time of the arrest. An arresting officer’s state of mind, except for the facts that the arresting officer knows, is irrelevant to the existence of probable cause. A rule that the offense establishing probable cause must be closely related to, and based on the same conduct as, the offense identified by the arresting officer at the time of arrest is inconsistent with these principals. Devenpeck v. Alford, 543 U.S. 146, 125 S. Ct. 588, 160 L. Ed. 2d 537 (2004).

For a conditioned anticipatory warrant to comply with the 4th amendment’s requirement of probable cause, two prerequisites of probability must be satisfied. It must be true not only that if the triggering condition occurs there is a fair probability that contraband or evidence of a crime will be found in a particular place, but also that there is probable cause to believe the triggering condition will occur. The triggering condition for an anticipatory search warrant need not be set forth in the warrant itself. United States v. Grubbs, 547 U.S. 90, 126 S. Ct. 1494, 164 L. Ed. 2d 195 (2006).

Valid warrants will issue to search the innocent, and people unfortunately bear the cost. Officers executing search warrants on occasion enter a house when residents are engaged in private activity, and the resulting frustration, embarrassment, and humiliation may be real, as was true here. When officers execute a valid warrant and act in a reasonable manner to protect themselves from harm, however, the 4th amendment is not violated. Los Angeles County v. Rettele, 550 U.S. 609, 127 S. Ct. 1989, 167 L. Ed. 2d 974 (2007).

To determine if the “alert” of a drug-detection dog during a traffic stop provides probable cause to search a vehicle, the state need not present an exhaustive set of records. A probable-cause hearing focusing on a drug-sniffing dog’s alert should proceed much like any other probable-cause hearing. The question—similar to every inquiry into probable cause—is whether all the facts surrounding a dog’s alert, viewed through the lens of common sense, would make a reasonably prudent person think that a search would reveal contraband or evidence of a crime. A sniff is up to snuff when it meets that test. Florida v. Harris, 568 U.S. 237, 133 S. Ct. 1050, 185 L. Ed. 2d 61 (2013).

911 calls are not per se reliable. However, given the technological and regulatory developments in the 911 system, a reasonable officer could conclude that a false tipster would think twice before using such a system. A caller’s use of the 911 system in this case was one of the relevant circumstances that justified the officer’s reliance on the information reported in the 911 call. Navarette v. California, 572 U.S. 393, 134 S. Ct. 1683, 188 L. Ed. 2d 680 (2014).

A mistake of law can give rise to the reasonable suspicion necessary to uphold a seizure under the 4th amendment. In this case, an officer stopped a vehicle because one of its two brake lights was out, but a court later determined that a single working brake light was all the law required. Because the officer’s mistake about the brake-light law was reasonable, the stop in this case was lawful. Heien v. North Carolina, 574 U.S. 54, 135 S. Ct. 530, 190 L. Ed. 2d 475 (2014).

Pretrial detention can violate the 4th amendment not only when it precedes, but also when it follows, the start of legal process in a criminal case. The 4th amendment prohibits government officials from detaining a person in the absence of probable cause. That can happen when the police hold someone without any reason before the formal onset of a criminal proceeding. But it also can occur when legal process itself goes wrong—when, for example, a judge’s probable-cause determination is predicated solely on a police officer’s false statements. Legal process does not expunge a 4th amendment claim when the process received by the defendant failed to establish what that amendment makes essential for pretrial detention—probable cause to believe the defendant committed a crime. Manuel v. City of Joliet, 580 U.S. 357, 137 S. Ct. 911, 197 L. Ed. 2d 312 (2017).

The totality of the circumstances test requires courts to consider the whole picture and to determine whether a reasonable officer could conclude—considering all of the surrounding circumstances, including the plausibility of the explanation itself—that there was a substantial chance of criminal activity. District of Columbia v. Wesby, 583 U.S. 48, 138 S. Ct. 577, 199 L. Ed. 2d 453 (2018).

An officer making an arrest at a suspect’s home pursuant to a warrant, after the suspect opens the door, can arrest for a narcotics violation based on narcotics in plain sight in the room. Schill v. State, 50 Wis. 2d 473, 184 N.W.2d 858 (1971).