Wis. Stat. § 343.303
If a law enforcement officer has probable cause to believe that the person is violating or has violated s. 346.63(1) or (2m) or a local ordinance in conformity therewith, or s. 346.63(2) or (6) or 940.25 or s. 940.09 where the offense involved the use of a vehicle, or if the officer detects any presence of alcohol, a controlled substance, controlled substance analog or other drug, or a combination thereof, on a person driving or operating or on duty time with respect to a commercial motor vehicle or has reason to believe that the person is violating or has violated s. 346.63(7) or a local ordinance in conformity therewith, the officer, prior to an arrest, may request the person to provide a sample of his or her breath for a preliminary breath screening test using a device approved by the department for this purpose. The result of this preliminary breath screening test may be used by the law enforcement officer for the purpose of deciding whether or not the person shall be arrested for a violation of s. 346.63(1), (2m), (5) or (7) or a local ordinance in conformity therewith, or s. 346.63(2) or (6) , 940.09(1) or 940.25 and whether or not to require or request chemical tests as authorized under s. 343.305(3) . The result of the preliminary breath screening test shall not be admissible in any action or proceeding except to show probable cause for an arrest, if the arrest is challenged, or to prove that a chemical test was properly required or requested of a person under s. 343.305(3) . Following the screening test, additional tests may be required or requested of the driver under s. 343.305(3) . The general penalty provision under s. 939.61(1) does not apply to a refusal to take a preliminary breath screening test.
Wis. Stat. § 343.303
A prosecutor's statement that the defendant failed a preliminary breath test was improper, but evidence that the defendant refused to take a breathalyzer test was relevant and constitutionally admissible. State v. Albright, 98 Wis. 2d 663, 298 N.W.2d 196 (Ct. App. 1980). A preliminary breath test result is not determinative of probable cause to arrest for driving while intoxicated. A low test result does not void the grounds for arrest. Dane County v. Sharpee, 154 Wis. 2d 515, 453 N.W.2d 508 (Ct. App. 1990). The bar of preliminary breath tests under this section is limited to proceedings related to arrests for offenses contemplated under this statute including those related to motor vehicles and intoxication. State v. Beaver, 181 Wis. 2d 959, 512 N.W.2d 254 (Ct. App. 1994). This section bars the evidentiary use of preliminary breath test results in motor vehicle violation cases, but not in other actions. Prosecutors who wish to rely on PBT results are required to present evidence of the device's scientific accuracy as a foundation for admission. State v. Doerr, 229 Wis. 2d 616, 599 N.W.2d 897 (Ct. App. 1999), 98-1047. "Probable cause to believe" refers to a quantum of evidence greater than reasonable suspicion to make an investigative stop, but less than probable cause to make an arrest. County of Jefferson v. Renz, 231 Wis. 2d 293, 603 N.W.2d 541 (1999), 97-3512. Blood may be drawn in a search incident to an arrest for a non-drunk-driving offense if the police reasonably suspect that the defendant's blood contains evidence of a crime. This section does not prohibit the consideration of a suspect's refusal to submit to a PBT for purposes of determining whether a warrantless involuntary draw of the suspect's blood was supported by reasonable suspicion. State v. Repenshek, 2004 WI App 229, 277 Wis. 2d 780, 691 N.W.2d 369, 03-3089 A preliminary breath test may be requested when an officer has a basis to justify an investigative stop but has not established probable cause to justify an arrest. Under the facts of this case, the officer would have been justified in asking the defendant to take a preliminary breath test without asking him to perform any field-sobriety tests. That the defendant successfully completed all properly administered field-sobriety tests did not subtract from the common-sense view that the defendant may have had an impermissible blood-alcohol level. State v. Felton, 2012 WI App 114, 344 Wis. 2d 483, 824 N.W.2d 871, 11-2119. Under State v. St. George, 2002 WI 50, for a defendant to establish a constitutional right to the admissibility of proffered expert testimony, the defendant must satisfy a two-part inquiry determining whether the evidence is clearly central to the defense and the exclusion of the evidence is arbitrary and disproportionate to the purpose of the rule of exclusion, so that exclusion undermines fundamental elements of the defendant's defense. In an OWI prosecution, even if a defendant establishes a constitutional right to present an expert opinion that is based in part on PBT results, the right to do so is outweighed by the state's compelling interest to exclude that evidence. State v. Fischer, 2010 WI 6, 322 Wis. 2d 265, 778 N.W.2d 629, 07-1898. But see Fischer v. Ozaukee County Circuit Court, 741 F. Supp. 2d 944 (2010). Probable cause exists to request a preliminary breath test sample when the driver is known to be subject to a .02 prohibited alcohol content standard, the officer knows it would take very little alcohol for the driver to exceed that limit, and the officer smells alcohol on the driver. State v. Goss, 2011 WI 104, 338 Wis. 2d 72, 806 N.W.2d 918, 10-1113. The Wisconsin Supreme Court's decision in Fischer affirming the exclusion of the defendant's expert's testimony using PBT results involved an unreasonable application of federal law as determined by the United States Supreme Court. Fischer v. Ozaukee County Circuit Court, 741 F. Supp. 2d 944 (2010).