> In France, the Cour d’assises itself was inherited from the French Revolution. Since a law of 1941, it is a mixed jury system, meaning that lay citizens sit together with professional judges
That kind of stuff makes me profoundly uncomfortable. Presumably, too, since the judge doesn't participate in the jury deliberations at all, the (un)credibility of said expert witness never saw the light of day. Did the accused's side raise that possibility during cross-examination at all?
You are not allowed to use your own expertise that is not presented in the trial to inform your decisions.
That is by law. Or at least, it was in Massachusetts when I last served on a jury. Which brought me to actual tears, btw, because the eyewitness testimony was being weighed too heavily.