The police have eight breathalyzer machines and have discovered that five of them were not calibrated correctly, giving false readings.
1,147 cases were affected between September, 2009 and November, 2010. The issue came to light when defense attorney Charles Peruto raised an objection in court to a questionable breathalyzer result. He predicts there may be as many as 5,000 tainted cases and most of those defendants will walk.
The news brought a reaction we don't often hear from the people in charge.
"We screwed up folks. We screwed up, plain and simple, and now we're paying for it," said Ramsey.
Philadelphia District Attorney Seth Williams says every defendant who's been convicted will have their sentence vacated given a new trial if they want. He added, however, even without breathalyzer results, many of those convictions will stand based on police testimony and other factors, including blood tests.
"In some of those cases we will be able to continue and, we believe, we'll be able to get a second conviction if necessary based on the police officer's observations," said Williams."
Peruto said, don't count on it.
"They don't even perform them any longer and they are not trained to do it. They've relied so heavily on the results of these machines that you don't have any corroboration," Peruto said.
At this point, authorities don't know how many convictions could be thrown out, but it leaves open the possibility that dangerous drivers may be back on the road.
Innocent defendants may also have been jailed, leaving open the possibility of costly lawsuits against the city.
Commissioner Ramsey says an internal investigation is underway.
"There's one person who is responsible for calibrating these machines. The error was human error, and it is inexcusable. Period. It should not have happened," said Ramsey.
Philadelphia police have stopped doing breathalyzer tests for the time being. A state police expert is in Philadelphia going over all eight machines to make sure they're are calibrated correctly before they go back in service.