Falcons claimed 30-year-old former Marine Perry, who joined Newcastle from Plymouth earlier this year, was acting in self-defence before being dismissed by leading English referee Tony Spreadbury.
And the three-man panel, sitting in Coventry on Tuesday night, accepted that Perry's offence was committed under extreme provocation and in self-defence.
He was found guilty, though, and was suspended until November 16, ruling him out of European Challenge Cup games against Brive and Borders, plus Premiership appointments with Gloucester and London Irish.
Newcastle have until Wednesday night to decide on a possible appeal, while Perry was also ordered to pay Â£250 costs towards the hearing.
The ban concluded a miserable day for Newcastle, who announced just a few hours earlier that their long-serving prop Ian Peel had been forced to retire because of a neck injury.
With Perry's hearing concluded, England World Cup-winner White entered the dock well after 10pm to face the same panel, chaired by RFU Council member Richard Moon.
White, who was sent off in the same incident for punching Perry, later received an eight-week ban.
White's suspension means that he cannot play again until December 12, sidelining him from eight matches, including four Premiership games and two European Cup clashes.
White pleaded guilty at the hearing and he had already publicly apologised for his actions.
Leicester have until 9pm Wednesday to decide on any appeal, but it could be that they will now draw a line under the episode, especially given that White could conceivably have been banned for a lot longer.