Conduct engaged in by a public servant in the course of official duty is justified if it is required or authorized by law.
A person who has been directed by a public servant to assist that public servant is justified in using force to carry out the public servant's direction unless the action directed by the public servant is plainly unlawful.
If a public servant authorized to make an arrest or prevent an escape is not available, a person is justified in using force upon another to effect the arrest or prevent the escape if [the other person has committed, in the presence of the Defendant, any crime which the Defendant is justified in using force to prevent] [the other person has committed a felony involving force or violence].
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