But you already knew all of this, of course.
Answer the question, please: "Why on earth would you expect me to believe anything stated by a demonstrable liar?"
So about your question - he's a demonstrable liar if:
1. We make up a new definition for amnesty
2. We decide what McCain originally supported was equal to what President Reagan (presumed not to be a demonstrable liar, since you hold him up as the paragon of Presidential ability) actually supported and signed into law
3. We ignore that McCain has chosen to change his mind, and that by changing one's mind you become a liar
So I guess you're a demonstrable liar too, since your own post here and the link you used falsely states the man's own statements and positions?
So I guess in a roundabout way is that I can't answer the question because the premise of the question itself is false - the questioner is the liar, in this case.