There is no evidence that they did. Even the Colts footballs that started the game at 13.x PSI were below tolerance at halftime (3 of 4 measured).
Two studies, Head Start Labs, an offshoot of Carnegie Mellon (
video here,
report here) and
AEI found there to be NO PHYSICAL EVIDENCE FOR DEFLATION.
Smart Labs found that a wet ball plus colder conditions easily accommodate the pressure differential in the Patriots footballs. AEI found that tortured mathematics aside, the measurements taken at halftime (if you account for warming that occurred while they were measuring and re-inflating, 13 minutes in a room 20+ degrees warmer than outside) show that the Patriots and Colts balls experienced the same effects from the wet and cold conditions and that the loss of pressure, applied in reverse, was consistent with pregame measurements that showed the Pats footballs at 12.5 and the Colts at just over 13.0.
There is no physical evidence of a crime.