ESPN has a major piece out titled “Spygate to Deflategate: Inside what split the NFL and Patriots apart”, which attempts to quantify the degree of New England Patriots cheating leading up to the Spygate scandal and how the light penalties the team received impact the NFL’s actions in Deflategate. The portion of the story of local interest:

The Patriots’ primary victims saw Spygate, and other videotaping rumors, as confirmation that they had been cheated out of a Super Bowl — even though they lacked proof. The Panthers now believe that their practices had been taped by the Patriots before Super Bowl XXXVIII in 2004. “Our players came in after that first half and said it was like [the Patriots] were in our huddle,” a Panthers source says. During halftime — New England led 14-10 — Carolina’s offensive coordinator, Dan Henning, changed game plans because of worries the Patriots had too close a read on Carolina’s schemes. And, in the second half, the Panthers moved the ball at will before losing 32-29 on a last-second field goal. “Do I have any tape to prove they cheated?” this source says. “No. But I’m convinced they did it.”