There is no rule about altering the balls to spec

[upstater1]

http://www.ibtimes.com/did-tom-brady-cheat-breaking-down-nfl-ball-rules-deflategate-1912383

Apparently, there is no rule that says a ball can't be deflated to 12.5 PSI

 

[QuantumMechanic]

It says "The Referee shall be the sole judge as to whether all balls offered for play comply with these specifications."

So once the referee approves the balls, how do you view that sentence as giving McNally the right to change the pressure in the balls?