Pennsylvania Consolidated & Unconsolidated Statutes
Chapter 5 - General Principles of Justification
Section 508 - Use of force in law enforcement

(a) Peace officer's use of force in making arrest.--
(1) A peace officer, or any person whom he has summoned or directed to assist him, need not retreat or desist from efforts to make a lawful arrest because of resistance or threatened resistance to the arrest. He is justified in the use of any force which he believes to be necessary to effect the arrest and of any force which he believes to be necessary to defend himself or another from bodily harm while making the arrest. However, he is justified in using deadly force only when he believes that such force is necessary to prevent death or serious bodily injury to himself or such other person, or when he believes both that:
(i) such force is necessary to prevent the arrest from being defeated by resistance or escape; and
(ii) the person to be arrested has committed or attempted a forcible felony or is attempting to escape and possesses a deadly weapon, or otherwise indicates that he will endanger human life or inflict serious bodily injury unless arrested without delay.
(2) A peace officer making an arrest pursuant to an invalid warrant is justified in the use of any force which he would be justified in using if the warrant were valid, unless he knows that the warrant is invalid.
(b) Private person's use of force in making arrest.--
(1) A private person who makes, or assists another private person in making a lawful arrest is justified in the use of any force which he would be justified in using if he were summoned or directed by a peace officer to make such arrest, except that he is justified in the use of deadly force only when he believes that such force is necessary to prevent death or serious bodily injury to himself or another.
(2) A private person who is summoned or directed by a peace officer to assist in making an arrest which is unlawful, is justified in the use of any force which he would be justified in using if the arrest were lawful, unless he knows that the arrest is unlawful.
(3) A private person who assists another private person in effecting an unlawful arrest, or who, not being summoned, assists a peace officer in effecting an unlawful arrest, is justified in using any force which he would be justified in using if the arrest were lawful, if:
(i) he believes the arrest is lawful; and
(ii) the arrest would be lawful if the facts were as he believes them to be.
(c) Use of force regarding escape.--
(1) A peace officer, corrections officer or other person who has an arrested or convicted person in his custody is justified in the use of such force to prevent the escape of the person from custody as the officer or other person would be justified in using under subsection (a) if the officer or other person were arresting the person.
(2) A peace officer or corrections officer is justified in the use of such force, including deadly force, which the officer believes to be necessary to prevent the escape from a correctional institution of a person whom the officer believes to be lawfully detained in such institution under sentence for an offense or awaiting trial or commitment for an offense.
(3) A corrections officer is justified in the use of such force, which the officer believes to be necessary to defend himself or another from bodily harm during the pursuit of the escaped person. However, the officer is justified in using deadly force only when the officer believes that such force is necessary to prevent death or serious bodily injury to himself or another or when the officer believes that:
(i) such force is necessary to prevent the apprehension from being defeated by resistance; and
(ii) the escaped person has been convicted of committing or attempting to commit a forcible felony, possesses a deadly weapon or otherwise indicates that he will endanger human life or inflict serious bodily injury unless apprehended without delay.
(d) Use of force to prevent suicide or the commission of crime.--
(1) The use of force upon or toward the person of another is justifiable when the actor believes that such force is immediately necessary to prevent such other person from committing suicide, inflicting serious bodily injury upon himself, committing or consummating the commission of a crime involving or threatening bodily injury, damage to or loss of property or a breach of the peace, except that:
(i) Any limitations imposed by the other provisions of this chapter on the justifiable use of force in self-protection, for the protection of others, the protection of property, the effectuation of an arrest or the prevention of an escape from custody shall apply notwithstanding the criminality of the conduct against which such force is used.
(ii) The use of deadly force is not in any event justifiable under this subsection unless:
(A) the actor believes that there is a substantial risk that the person whom he seeks to prevent from committing a crime will cause death or serious bodily injury to another unless the commission or the consummation of the crime is prevented and that the use of such force presents no substantial risk of injury to innocent persons; or
(B) the actor believes that the use of such force is necessary to suppress a riot or mutiny after the rioters or mutineers have been ordered to disperse and warned, in any particular manner that the law may require, that such force will be used if they do not obey.
(2) The justification afforded by this subsection extends to the use of confinement as preventive force only if the actor takes all reasonable measures to terminate the confinement as soon as he knows that he safely can, unless the person confined has been arrested on a charge of crime.
(July 17, 2007, P.L.139, No.41, eff. 60 days)

2007 Amendment. Act 41 amended subsec. (c).
Cross References. Section 508 is referred to in section 8340.2 of Title 42 (Judiciary and Judicial Procedure).