There are also two comments, by 'Mack' and 'Paul' that I believe hit the nail on the head. Lawyers make laws for their own self-interest and the Courts, which are of course composed entirely of lawyers, interpret laws so as to benefit their own profession. I was having lunch today and a friend made the comment that lawyers don't know right from wrong and don't really care either - they only care what the loopholes in the law as regards any given case allow them to do.
I agree that lawyers should not be allowed to serve at any level of government. But I would go one step further. The Supreme Court needs to lose its designated status as the sole arbiter of what the Constitution does or does not mean. In short, if the Court says one thing and the President and Congress disagree, then the Court's opinion is rendered moot. In short, any two branches of government should be able to over-ride the third. The three branches are equal - the Court is not superior to Congress according to the Constitution. And it is also time to stop looking at Supreme Court case law. The only law that matters is what the plain text of the Constitution and those treaties signed (and ratified) by the United States. Case law is made to be overturned - especially when it conflicts with the clear language of the Constitution (yes, I'm talking about Kelo, among many, many other instances of judicial over-reach).
In the end, lawyers are simply another special interest group. Are they a necessary evil? I'm actually not convinced of that. I think that if laws were written by people with common sense, then a lot of the difficulty in the law would vanish and the need for lawyers would lessen as well. Lawyers exist to make the law difficult to understand. if it were in plain English, as the Constitution is, then why would we need lawyers at all? The answer is, we probably wouldn't. And this is a state of affairs much to be desired.