That is why I said the optimal solution is a dead bad guy on the scene with no harmed good guys or girls.
If you want to take away the appeals process in case of murder, well...I'm sorry, that's a really dumb idea. There are already a ton of people convicted of very serious crimes on flimsy evidence that got all the way through the appeals process and were only much later exonerated through things like the innocence project: http://www.innocenceproject.org/
You can never get the years back, of course, but the idea of murdering innocent people because "well, being sure takes too long and costs too much" sounds like emotion, not reason, talking.
I have a lot of serious problems with the way our justice system is set up and run, anyway, making it "more streamlined and cheaper" is going to make that way worse.