Painter v. Harvey
United States Court of Appeals for the Fourth Circuit
863 F.2d 329 (4th Cir. 1988)
After officer Harvey (defendant) arrested Painter (plaintiff) for drunk driving, she publicly alleged he raped her and used excessive force, and Harvey counterclaimed for defamation based on those same public statements when Painter sued him under 42 U.S.C. § 1983 for lacking probable cause and using excessive force; the jury found for Harvey on both the federal claim and the state-law defamation counterclaim, and Painter moved to set aside the verdict, arguing the court lacked jurisdiction over the state-law counterclaim absent it being compulsory.
Whether a counterclaim is compulsory, and therefore within a federal court's supplemental jurisdiction, if the same evidence will support or refute both the original claim and the counterclaim.