In Federalist #57 (about half way) Madison argues that the House of Representatives will be restrained from passing "oppressive measures" since it will have to live under the laws that it passes. There is not one law for legislators and another for the people as a whole. It seems Obamacare violates that principle in that it may have removed current and future congressional members and staff from medical care coverage. As the NY Times put it, "The confusion raises the inevitable question: If they did not know exactly what they were doing to themselves, did lawmakers who wrote and passed the bill fully grasp the details of how it would influence the lives of other Americans?"
Once American politics becomes divorced from enlightened self-interest, the political process will violate rights. In this odd way, Obamacare proves this principle. It couldn't have happened to a more deserving group of people.
Second thought: Of course it's entirely possible that Congress exempted itself, because it thinks it can get a better deal through other means. In either case, debate over extending coverage will prove most revealing.