First point: Lifetime appointments for Supreme Court Justices is a policy that  should be reviewed.  The founding fathers never expected Supreme Court Justices to live into their nineties.
Second point: We seem to live in a society where people think they can do whatever they want, that anything is OK, if they can get away with it.  That's true for people who drive 30 mph over the speed limit; that's true for kids who cheat on tests, and it's true for Presidents and Vice Presidents who commit war crimes. It's astonishing to me how much damage the Bush administration has done to this country in such a relatively short period of time. Their crimes are much more than matters of poor judgement, irresponsibility, and failed policies. They have lied, cheated, and broken laws to carry out their own agendas regardless of ethics, morality or legality. Bush and Cheney spent eight years doing whatever they thought best, regardless of the harm done to Americans here at home and the harm done to the US abroad. They have freely, and proudly, admitted that they authorized torture. Not to investigate and prosecute them for committing war crimes is an injustice to to other countries and it's an injustice to us. We cannot put ourselves in the position of continuing a policy, as a nation in the world community, of doing whatever we please. Not to hold Bush and Cheney accountable for the crimes they have committed sends a message to the rest of the world that the U.S. is, even after the Bush administration, a law unto itself. That the rules don't apply to us. We can't expect the respect and trust of the rest of the world if we don't do the right thing by showing that we know the unforgiveable has been done and that we will not stand for it. And we need to show ourselves, especially our kids, that the rules apply to everybody. That being rich or powerful does not give anybody a pass to ignore the law. That there are repercussions. That they will be held accountable.  If the law doesn't apply to everybody equally, what does that say about our democracy?