But the criminal justice system isn't about truth. It's about evidence and proving a case beyond reasonable doubt. I wish it was about finding truth, but it is a battle of arguments, motions, credibility and admissibility.
And no one, especially an officer of the court, should be considered "privileged". It makes a mockery of a system that is sometimes already a mockery of justice.
But I do agree with you that that is precisely why she wasn't charged. I'm sure there will be civil lawsuits up the wazoo after this.