Don't you care about the Charter?

Paul Martin has been wrapping himself in the Charter, and defending his position by saying that the Prime Minister cannot pick and choose which Charter rights he will defend. But I have a question. A few years ago there was a vote in the House of Commons affirming the traditional definition of marriage. Paul Martin voted in favour of it. Fast forward a couple of years, and Paul Martin did everything he could to change the legal definition of marriage citing the Charter. My question is this... when did Paul Martin first read the Charter? Was it after he voted in favour of the traditional definition of marriage? Did he not believe in the Charter back then? What has changed? Why does he wrap himself in the Charter now, and cast himself as the defender of Charter rights?