From that Gore speech today:

A president who breaks the law is a threat to the very structure of our government. Our Founding Fathers were adamant that they had established a government of laws and not men. Indeed, they recognized that the structure of government they had enshrined in our Constitution – our system of checks and balances – was designed with a central purpose of ensuring that it would govern through the rule of law. As John Adams said: “The executive shall never exercise the legislative and judicial powers, or either of them, to the end that it may be a government of laws and not of men.”