Another test which I think has been done on rare occasions is measuring the inter-rater reliability between different juries (which could be done by having seve

Another test which I think has been done on rare occasions is measuring the inter-rater reliability between different juries (which could be done by having several juries hear the same trial and then deliberating independently). (It's harder to do this with judges if the judges are also overseeing the trial and ruling on evidentiary and procedural matters.)