Wow. Well...ummm...okay.
A bit extreme...but I get your point.
I wonder if the lesson could be taught without the executions and stringing of bodies, though.
Personally, I don't think there's anything short of physical harm that could be done to these people to stop them from doing what they do, or deter others from acting the same way.
Did you ever see The Dark Knight Rises? There's a scene where Scarecrow holds a court and they try the greedy, disgusting, corrupt wealthy assholes in what is basically a court in front of the people, then they sentence them to walk along the ice until they reach the other side, or fall through into the water. Something like that would have been deeply satisfying for the American people and it would have deterred future instances of intentional fraud.