The Pryce/Huhne sentence seems to be fair and just to me.
Perverting the course of justice. It does what it says on the tin. Like perjury, the justice system takes a very dim view of people who take the Michael out of the justice system by lying. If they don’t impose sentences which provide a warning and deterrent to others, then the whole system falls apart and anarchy reigns.
This wasn’t just a case of someone taking the other’s points, it was lying about it afterwards and swearing blind they didn’t do it.