And how do we know whether a forced confession is true? False confessions do happen under other circumstances. Obviously, if the subject reveals something backed by evidence they wouldn't have known being innocent, that's one thing. But if we're using their confession as the evidence, then it's the same problem as any forced confession.

There's a great book called "The Memory Illusion" by Dr. Julia Shaw

http://www.memoryillusion.com/

It's very easy to get false convictions, and to make people believe false memories. There have been widely replicated experiments.

There are two different answers depending on who you ask.

The more ignorant will answer: it’s obviously true because they confessed. Nobody would confess to a crime they didn’t commit.

The more evil answer is: who cares? The public is reassured by a self-admitted criminal going to prison and I get re-elected.

Right, and both work until the conviction is overturned, the media makes a big deal out of it, and the Justice System is called into question yet again. Or it's not overturned, and someone makes a documentary followed by a dozen podcasts and online petitions. Which again calls into question how just the Justice System is, and how impartial a jury of your peers really is.

The Generation Why podcast will occasionally raise the point that if you try the same case more than once, you often get different results. Which really raises questions. Why didn't the judge allow certain information into the trial the first time, but another judge did the second time? How was the prosecution able to withhold information from the defense? Why on Earth did the jury find the defendant guilty despite no evidence tying them to the crime? Or in some cases, the opposite is true. How did the jury find the defendant innocent with that much evidence against them?

And the real perpetrator is never caught.

Not at all.

Any information you receive verbally from a single source is not very reliable regardless of how it was obtained.