What makes you think a jury is by definition "angry and easily manipulable"? This says a lot more about your view of humanity and yourself than it does jury trials.
Yes, i do believe individual humans are way less perfect agents than some free will devotees make them out to be. Making good decisions is expensive... requires both time and prior knowledge/influences. Something someone forced to do jury duty is unlikely to bring. They spend their resources to be experts in other fields.
Btw, if you wanted to go into the free will vs formed by society thing: The reason parents tell their children to "work hard" and "be responsible for them self" is this being an effective influence. Such is necessary by society to provide for people to become better individuals. I know it sounds contradictory at first.
But your argument is also applicable to judges. There's nothing in legal training that makes people magically superior to "normies", incapable of error and so on.
Meanwhile someone forced to do jury duty is gonna spend the time there whether they like it or not, so there's also no motivation to _not_ try to make good decisions. It won't save any time.
