American Political Jurisdiction

I find it fascinating and a point that I had never really thought about which is we elect those who preside over political jurisdiction in the United States but in other places they don't do that. I find it very weird to have a fair trial when the jurors are not elected by the people but rather entitled. In that same light, I guess it would be easy to bias a judge or those who preside and offer jurisdiction when they are elected. That is just my pondering, and it is an interesting thing to ponder.