State v. McFadden
Iowa Supreme Court
320 N.W.2d 608 (1982)
Michael McFadden (defendant) and Matthew Sulgrove engaged in a drag race; Sulgrove lost control, swerved into oncoming traffic, and struck another car, killing himself and a girl in that car. McFadden's car never physically touched either vehicle. Convicted of two counts of involuntary manslaughter under theories including aiding and abetting, vicarious liability for joint drag racing, and direct proximate causation, McFadden appealed, arguing the causation element was missing since his car caused no contact.
Whether the acts and omissions of two or more persons may work concurrently as the efficient cause of an injury, such that each person's reckless act or omission is regarded as a proximate cause in a criminal prosecution.