Eleven-year-old Rhys Jones's killer's mum has been found guilty of perverting the course of justice, and is almost certainly facing a custodial sentence.
Which is fair enough - it's a completely open-and-shut case, she's guilty as hell, and prison is necessary as a powerful disincentive...
...but I'm fascinated by the psychology behind it. At some point during the investigation, even if she didn't know all along, she must have realised with total and absolute certainty that her son did it. And I suspect she'd also have been warned upfront about the penalties for perjury - certainly, when I did jury service and a defence witness told a story that blatantly didn't fit the established facts, the prosecuting counsel brought up the subject. (Come to think of it, he was the defendant's dad).
So how on earth do you process something like this, given that you're quite literally damned if you do and damned if you don't? (i.e. "doing the right thing" means your son being banged up for murder, as well as the threat of possible reprisals from his associates).