You'd still have people being paid under the system I'd like to see; they simply would be paid for determining facts, as opposed to being paid for trying to put people in prison whatever the facts might be. I'd view that as an improvement...
Judges determine facts. Not govt lawyers. Nifong wouldn’t have executed anyone.
Here’s a better solution instead of your utopian one. If anyone illegally causes the death of another; lying cops and prosecutors included, they get it in the neck as well.
Lastly, Perfection is the enemy of good.