Let's say I'm a defense lawyer and my client is a criminal that killed 50 people so far, but got away with it every single time, and he's on trial for a 51st, which he's also poised to escape because there's no evidence pointing directly to him.
As his lawyer, he told me about all of his murders, and he gave me information that the police can verify that can link him to all 51 murders.
Here's a concrete example: he took a video of all of his murders, and he hid all the recordings so that the police cannot find them, but he told me (his lawyer) about them and exactly where they are.
If I break client confidentiality and tell the police everything I know, and give them all the evidence they need to 100% link him to all 51 crimes, is he going to walk free because I "didn't follow procedure"?
If so, then the legal system is really effed up...
Just a little discussion I had with a friend, neither of us have any legal education.