For centuries, the House of Lords has been Britain's highest court. But no longer. The law lords have delivered their last judgment - an appropriately landmark one, about assisted suicide. In October, our top judges will form Britain's new Supreme Court, our new final domestic court of appeal.

Traditionalists have condemned the changes, but they mark the end one of Britain's most blatant infringements of the principle of the separation of powers – that judges should be separate from the executive and legislature. The Labour government has been under constant criticism during 2009, not least from me, but it deserves great credit for this historic change.