"Somebody tampered with the balls," said Berger. "And made it so it was easier to squeeze for the Patriots."
Earlier this week news broke that 11 of the 12 footballs used by the Patriots during the game against the Indianapolis Colts were under-inflated, which Berger said makes them easier to catch and hold.
Footballs are officially meant to be inflated to 13 pounds of pressure per square inch, or psi. All the balls are checked two hours before the game.
The balls at the AFC championship game were only 11 psi, the preferred pressure of quarterback Tom Brady, who plays for the Patriots.
"Somebody knows that Tom Brady likes the ball that way and somebody adjusted the footballs," said Berger.
Berger, who won the Super Bowl XLIII with the Pittsburgh Steelers in 2008 and has also played for the Philadelphia Eagles, Minnesota Vikings and Denver Broncos, said quarterbacks each have their preferences for football pressure.
"Some quarterbacks want it to be bigger and fatter," said Berger.
Brady denies knowledge of deflated balls
Tom Brady has denied having any knowledge of the ball being tampered with.
Berger said Patriots manager Bill Belichick is known to be aware of everything that's going on with his team and his players.
But he also said quarterbacks are the ones who deal with the equipment managers to make sure the ball is the way they want it.
He added that all the balls brought to the game and used by the Colts were still 13 psi, so it's unlikely the Patriots' footballs were deflated because of cold weather.
"There's no way the balls got from 13 to 11 pounds without somebody doing it for the benefit of Tom Brady, whether he admits it or not," said Berger. "It's just impossible."
To listen to the full interview with Mitch Berger, click on the audio labelled: Former NFL kicker Mitch Berger gives his take on deflate-gate