Wayne Lucas, Guy Eagleton and David Bartle alleged Peter Penny assaulted them. His outburst triggered a swift reaction from the men overseeing the police cells: Wayne Lucas, Guy Eagleton and David Bartle. Two grabbed him by the arms, and the third put him in a headlock. They carried him down the corridor towards Cell 3. The Corrective Services officers alleged this is what happened next: Penny became abusive and aggressive. He spat at them, lunged at them several times, and eventually landed a punch on the left hand side of Lucas's face. ''Penny is … abusive and carrying on like a treat, just abusing us, swearing at us, threatening us,'' Lucas said in court under oath. ''He kept on coming forward towards us. I did push back once and we told him that we're leaving the cell. But that's when he … got up and had a bit of a swing at me and hit me in the side of the face.'' Lucas said Penny had threatened him by saying he knew where Lucas ate lunch each day. ''I felt very, you know, upset and very scared about it,'' Lucas said.

Ten charges were laid against Penny of assault, resisting arrest and intimidation, and he languished in jail for three months, waiting to have the charges heard in court. In May 2008, a magistrate, Peter Bugden, heard a full day's evidence in the Penrith Local Court, including Lucas's testimony. The big problem was the video evidence. Somehow, the tape provided to the court had scrambled; each second it showed a kaleidoscope-like picture of seven images from the cameras dotted throughout the police station. It was ''one of the most unhelpful tapes I've ever seen in my life'', the magistrate said. Penny was released on bail by July 2008, but it was not until January 2009 that the matter returned to court. In that time, Stephen Robson, Penny's defence barrister, managed to isolate pictures from just the cameras inside and immediately outside Cell 3. He gave the new tape to the police prosecutor, Leo Jajaw, who was so surprised by the evidence he told the magistrate: ''I won't be offering any further evidence.''

In other words, officers Eagleton and Bartle would not be called to give evidence. All 10 of the charges of assault and intimidation against Penny were dismissed. The tape was unequivocal. Penny was charged into the cell in a headlock and then thrown across the room. His mattress and blanket were confiscated. Eagleton and Bartle hovered by the entrance to the cell, and Lucas could be seen clearly throwing four punches at Penny. In one frame, Penny was cowering against the wall of the cell with his arms folded in front of his face as Lucas adopted a boxing stance, his right fist cocked and ready. Penny's barrister was scathing about the version of events first given to the court by Lucas: ''The submission will be his evidence is worthless. It's so unreliable, to put it kindly, it's so unreliable that the court couldn't act on anything that came out of his mouth in the witness box.'' The magistrate agreed and threw out the case. The video ''portrays a different set of circumstances'' than Lucas did, he said. ''It appears to show Officer Lucas as the aggressor in several, can I call it, forays on the defendant. He is the one that approaches the defendant … it is quite clear on the evidence that Officer Lucas is the aggressor,'' Bugden ruled.

''The video evidence seems to fly in the face of his evidence. It not only does not support it, it goes contrary to the oral evidence that Officer Lucas gave … I do not regard what Officer Lucas was doing was acting in the exercise of his judgment. I do not accept his version of events.'' Remarkably, after the case was dismissed, one of the three Corrective Services officers lodged a formal complaint concerning the police prosecutor's actions in relation to the new tape. The complaint was ''resolved at a local management level'', a NSW Police spokesman said. The case came to light after the Herald published the details of confidential reports into the use of force against prisoners in the NSW jail system. They painted a damning picture of prison brutality and cover-up. They showed that since 1996 the Department of Corrective Services has been told repeatedly to produce records and preserve evidence on instances of violence by guards but has failed to do so. The documents suggested that as many as 1000 ''uses of force'' by guards occur across the prison system each year. When the Herald put questions about the Penny case to the department officials, they were unaware of the incident. A formal investigation has since been launched into the officers involved and the evidence that was given in court. ''CSNSW was not aware of the outcome of the prosecution of Peter Penny,'' a department spokeswoman said. ''We have no record of any referrals of the matter from NSW Police or any other agency … [nor] a record of any complaints made by Mr Penny which would certainly have been investigated.''

''The matter is now being referred to CSNSW Professional Conduct Management Committee for review.'' She said two of the officers were still employed as prison guards, but would not identify them. Do you know more? investigations@smh.com.au