PBT is a search subject to the Fourth Amendment. State v. Robinson, 2017 Kan. App. LEXIS 89 (Dec. 22, 2017):
The State also points out that the PBT is of limited evidentiary value and the results of the test are inadmissible in any civil or criminal action except to aid in determining a challenge to the validity of a DUI arrest. While this point may be true, it does not change the fact that a PBT constitutes a warrantless search conducted without probable cause and not incident to an arrest. Again, it is the statutory provision that criminalizes a person’s right to withdraw his or her consent to a search that runs afoul of constitutional safeguards. The screening test itself is not the problem provided that it is based on consent that can be deemed free and voluntary. Remove the criminal sanction for a test refusal and the PBT may well be a valid tool to combat drunk driving. Also, law enforcement officers still have a wide range of field sobriety tests that may be used to help determine whether there is probable cause to arrest a suspect for DUI.
There was probable cause for a PBT. Therefore, the court doesn’t reach the constitutionality of testing on reasonable suspicion. Fischer v. Kan. Dep’t of Revenue, 2017 Kan. App. LEXIS 93 (Dec. 29, 2017).*