The mother of three fell to the ground and bloodied her lip when Josey seemed to strike her from behind.
Josey, a 17-year veteran of the force, was charged with simple assault, but was acquitted during a bench trial in February. He contended that he had tried to knock a beer out of Guzman's hand.
The acquittal became a controversy onto itself when word spread afterward that Municipal Judge Patrick Dugan, who presided over the trial, was married to a Philly cop.
Yesterday's ruling, however, wasn't unexpected.
"We were confident the entire time," said John McNesby, the president of the Fraternal Order of Police Lodge 5, which appealed Josey's firing. "When we broke the video down, it was clear . . . that this girl had actually slipped, that she had not been hit, and that she bit her lip."
Josey's arbitration victory also didn't surprise Enrique Latoison, Guzman's attorney.
"We knew, after he got acquitted, that he'd get his job back," he said.
"It's very disappointing, but it's also very scary, as far as I'm concerned," Latoison added. "If you can get away with something like this on video, what's the limit?"
Guzman filed a civil lawsuit against the city, and was awarded a $75,000 settlement in May.
Ramsey said the arbitrator's ruling calls for Josey to be reinstated immediately to Highway Patrol - with back pay.
The commissioner has long complained about the arbitration process, which often swings in favor of the FOP.
McNesby, meanwhile, has criticized Ramsey in the past for firing officers who have been accused of wrongdoing before internal investigations are complete.
"I did what I felt was necessary. I have no regrets about that at all," Ramsey said of Josey's firing.
"Sometimes it goes in our favor, sometimes it doesn't," he said. "I think I made the right decision initially, and I have no plans to appeal the arbitrator's decision."
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