## Facts

- Around 3:00 a.m., a police officer patrolling a residential area heard loud yelling from behind a home and investigated.
- The officer saw Bruce Biagini staggering in and out of an alley and then encountered him in his backyard with an unidentified female.
- After the officer inquired, Biagini went inside; nearby individuals reported Biagini had been screaming and had thrown a glass bottle.
- The officer returned to Biagini’s door and asked him to come outside; Biagini refused and told the officer to leave.
- The officer told Biagini he was under arrest for public intoxication and disorderly conduct.
- When the officer attempted to arrest him, Biagini broke free and went back inside; after backup arrived, Biagini struggled with and punched the officer before being subdued.
- A lower appellate court later concluded the arrest for disorderly conduct/public intoxication lacked probable cause, but it still affirmed Biagini’s resisting-arrest conviction.

## Issues

1. Whether a defendant may be convicted of resisting arrest under 18 Pa.C.S. § 5104 when the underlying arrest is later determined unlawful for lack of probable cause.
2. Whether the illegality of an arrest permits a defendant to use force against a known police officer as self-defense/justification, affecting liability for assaultive offenses.

## Decision

- The Supreme Court of Pennsylvania held that a resisting-arrest conviction cannot stand if the underlying arrest is unlawful, because lawfulness is an element of 18 Pa.C.S. § 5104.
- The Court rejected any claim of a right to use force to resist a known police arrest, even if the arrest is unlawful, based on 18 Pa.C.S. § 505(b)(1)(i).
- The Court distinguished resisting arrest from aggravated assault: the illegality of the arrest defeats § 5104, but does not itself justify assaultive resistance or negate assault elements when the officer is performing official duties.
- The Court resolved inconsistent intermediate appellate rulings by adopting the interpretation that § 5104’s “lawful arrest” requirement is substantive.

## Legal Principles

- Under 18 Pa.C.S. § 5104, the Commonwealth must prove the defendant acted to prevent a public servant from effecting a lawful arrest; absence of probable cause defeats that element.
- A resisting-arrest conviction cannot be sustained when the underlying arrest is unlawful, because the statute expressly requires a lawful arrest.
- Under 18 Pa.C.S. § 505(b)(1)(i), force is not justifiable to resist an arrest the actor knows is being made by a peace officer, even if the arrest is unlawful.
- Pennsylvania law does not recognize a general right to resist arrest by force; challenges to arrest legality are to be pursued in court rather than through physical resistance.
- The unlawfulness of an arrest does not, by itself, supply a justification defense to assaultive conduct against an officer performing official duties.

## Conclusion

The court held that “lawful arrest” is a required element of resisting arrest under § 5104, so the offense fails if the arrest lacked probable cause; however, § 505(b)(1)(i) bars justification for using force to resist a known police arrest even when unlawful, leaving assault liability intact if its elements are proven.


Commonwealth v. Biagini, 655 A.2d 492 (Pa. 1995)