Looks like the standard practice was for the locker room attendant to deflate the balls right in the officials' locker room.  He said for a normal game that locker room is usually empty and he often sits in there and watches ESPN.  But because it was a Championship Game the officials' locker room was crowded and he had to take the bag of 24 balls into the rest room for doctoring. 

 

Those trying to scientifically explain away pressure changes for one game are purposely trying to deflect not only the one incident, but they ignore the damning "deflator" texts from earlier in 2014 and the fact that the "deflator" had chosen that nickname in 2013 or earlier, suggesting the deflation scheme was in place for previous years. 

 

Of course there is the history of Patriots' equipment personnel trying to slip doctored balls into games as early as 2004, and Brady's statements in 2006 about having "sleepless nights" wishing he had more control of the balls used on game days.  Then the lobbying effort by Brady and Manning to allow teams to bring their own pre-doctored balls for use on gamedays.  The new rule was adopted for the 2007 NFL season, and from then on, the Patriots' turnovers fell dramatically compared to league average, and remained significantly lower than any other teams' turnover ratio for 8 years. 

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