You fundamentally don't seem to agree with concept of the rule of law. And the rule of law is no way "abstract"- but utilitarian in preventing the abuses and tyranny of discretionary government. If that means some people that are ultimately guilty get off, so be it. It's a hell of alot better than your platonic bureaucrats that get discretionary power over people's life and death.
Back in 1957 in was the mafia that had the power over people's life and death. The got off the hook in 99% of the cases. So why worrying about their "rights being hurt" if in ONE case not everything went as they planned? Don't forget, it was 1957, not today, you still had problems like racial segregation for example, yet you insist that the "rights" of MOB BOSSES was the priority n.1 even back then?