In Law and Order, Arnold Kling describes his week on a jury for a murder trial. He makes a few interesting points in his conclusions:
Serving on a jury keeps ordinary citizens in touch with the awesome power of the state. We see how that power is used, and such visibility serves as a powerful check against abuse of power. In fact, thinking about this issue has me reconsidering my views on the all-volunteer army. War, too, is one of the most serious manifestations of the awesome power of the state. A professional army is a more effective army, just as a professional jury might be a more effective jury. However, there may be something to be said for keeping ordinary citizens aware first-hand of how the awesome power of the state is wielded in time of war.