The first time Hitler tried to seize power in Germany via a coup, he was arrested and used his trial to gain publicity, and rallied a lot of people towards his cause while he was in prison.
Which by the way, 20 people died in his coup attempt, something that would probably have made him eligible for the death penalty in the US (felony-murder doctrine) which had he been executed, it would have averted his eventual reign which itself lead to WWII.
And how many people dangerous to Those In Power would have been framed and killed by now as well?
It's too convenient a tool to get rid of political enemies.