Consider the evidence: Gonzales vs. Raich, the medicinal marijuana case recently decided by the Supreme Court.
A majority, which included the moderates and liberals on the court, ruled that the federal laws against medical marijuana are constitutional. Uphelding federal power over states' rights is consistent with their position.
Rehnquist, Thomas and O'Connor dissented on the basis of states' rights, which is also consistent with their position.
And where was Fat Tony, the "strict constructionist" and champion of states rights? In a surprise, he voted with mod/libs. Not because he agrees with the legal doctrine involved - but because he just doesn't want people to smoke pot. Or maybe he's just a fan of federal power when it's in the hands of the GOP?