Physics vs. Fishy Footballs

When it was reported that many of the footballs in the AFC Championship game were inflated below the required minimum pressure, the triumphant New England Patriots were accused of cheating. Looking for an explanation, Chad Orzel whipped out some footballs, a freezer, and the Ideal Gas Law to do some delving. Physically, air pressure depends on the volume of a gas, the number of molecules contained therein, and temperature. Since the volume of a football (versus a balloon) doesn't change much depending on how much air is inside, a change in temperature was the best chance for an innocent explanation. But Chad writes, "unless they did the pre-game testing of the balls in a sauna, or the post-game investigation in a meat locker, thermodynamics alone can’t get the Patriots off the hook." According to the Pats, they do some special mumbo jumbo to the outside of the balls before filling them to the required minimum pressure, after which the pressure settles down. Um, what? Chad writes that this explanation suggests the Patriots have "been preparing balls that were technically illegal for a long time." Underinflated balls are said to be easier to throw and catch, especially in the rain.