Hygh v. Jacobs
United States Court of Appeals for the Second Circuit
961 F.2d 359 (2d Cir. 1992)
During a confrontation, Officer William Jacobs (defendant) struck William Hygh (plaintiff) in the cheek, breaking his cheekbones and requiring plastic surgery; the parties disputed whether Jacobs struck Hygh in self-defense while both were standing, or while Hygh was bending down after being told he was under arrest. Hygh sued under §1983, and his expert witness on law enforcement, Terry Cox, testified that Jacobs used "deadly physical force" (which Cox defined as force with the potential to kill) that was "not warranted under the circumstances"; the jury found for Hygh, and Jacobs appealed the admission of Cox's testimony.
Whether an expert witness may testify to his own definition of a legal term of art and opine that a defendant's conduct was not legally warranted, when doing so effectively instructs the jury on the governing legal standard and the ultimate conclusion to reach.