I agree with C&SD. I do not advocate elimination of the death penalty, but I do have grave concerns about the ethics of the criminal "justice" system. The system only works if/when everyone involved plays by the rules. When cops start either hiding evidence or manufacturing evidence, when prosecutors pile on boatloads of charges in the hope that something will stick, and THEN withhold potentially exculpatory evidence from the defense ... heads should roll, and the heads should not be that of the defendant.
The problem is that the system has become focused on results, rather than on the process. Which is wrong, of course, because the law supposedly requires and supposedly guarantees "due process."
If the guy on trial is guilty but they got him to court by fabricating evidence and/or violating his rights, I would rather see him go free so that maybe down the road there won't be an innocent defendant on trial because of falsified evidence. But the police are under pressure to solve cases, not to respect the civil rights of less than stellar members of society. Prosecutors (too often) see their job as getting a conviction, not ensuring that justice is served.