Commonwealth v. Johnson, 624 Pa. 325

On March 8, 2010, Trooper Knott stopped a vehicle, ran passenger Richard Johnson’s name, and arrested him based on a computer "hit" showing an active arrest warrant.
During a search incident to arrest the trooper found suspected heroin (37 packets), two cell phones, and $1,674 in cash; Johnson was later Mirandized and made statements.
Trooper Knott later discovered the warrant had been served nine days earlier and should have been purged—i.e., the arrest warrant was expired/invalid at the time of Johnson’s arrest.
Johnson moved to suppress the physical evidence and post-arrest statements as fruits of an unlawful arrest; the trial court suppressed both under Article I, § 8 of the Pennsylvania Constitution.
The Superior Court affirmed suppression of the physical evidence (vacated suppression of statements); the Commonwealth appealed to the Supreme Court of Pennsylvania on the question whether a good-faith belief in a warrant’s validity precludes suppression.
The Pennsylvania Supreme Court affirmed the suppression of physical evidence, holding Edmunds controls and Pennsylvania does not recognize a Leon-style good-faith exception under Article I, § 8.

Issue	Plaintiff's Argument (Commonwealth)	Defendant's Argument (Johnson)	Held
Whether evidence seized incident to arrest on an invalid (expired) warrant is admissible where officers reasonably and in good faith believed the warrant was valid	Exclusion is inappropriate because the trooper reasonably relied on the warrant and Smith/Herring support admitting evidence when error was administrative and in good faith	Arrest lacked probable cause (warrant invalid); Edmunds forbids a state-law good-faith exception—privacy interests require suppression	Evidence suppressed: Pennsylvania follows Edmunds and Article I, § 8; no state good-faith exception applies to permit admission of physical evidence seized pursuant to an invalid arrest warrant

Commonwealth v. Edmunds, 526 Pa. 374, 586 A.2d 887 (Pa. 1991) (rejects a Leon-style good-faith exception under Pa. Const. art. I, § 8 and articulates state-constitutional analysis)
United States v. Leon, 468 U.S. 897 (U.S. 1984) (recognizes a federal good-faith exception to the Fourth Amendment exclusionary rule)
Herring v. United States, 555 U.S. 135 (U.S. 2009) (applies Leon reasoning to expired arrest warrants and conditions exclusion on systemic or reckless errors)
Commonwealth v. Smith, 606 Pa. 127, 995 A.2d 1143 (Pa. 2010) (held that statements after an arrest on an expired warrant can be admissible under attenuation/voluntariness analysis; did not decide state good-faith exception for physical evidence)
Commonwealth v. McFeely, 509 Pa. 394, 502 A.2d 167 (Pa. 1985) (sets factors for assessing attenuation between illegal arrest and confession)