Four days later, Lopez testified that Lawless "freaked out" and started punching and kicking him after he ordered her to the floor. On the basis of that testimony, a judge found probable cause for the charge against Lawless to proceed to trial.

While the witnesses in the convenience store (including her three friends who were also ordered to the ground for no apparent reason) would have supported Lawless' version of the encounter, juries tend to believe police officers. The charge against Lawless never made it to trial because four security cameras in the convenience store captured the incident. The photographic evidence contradicted Lopez' testimony.

The images show that when Officer Lopez entered the store, Lawless was at the counter, smiling and apparently unaware of his presence behind her. Lopez grabbed Lawless' neck from behind with his left hand, with his gun in his right hand. Lawless broke free and faced him.

"I was really confused," Lawless said in an interview. "I didn't know if we were getting robbed. I remember seeing his uniform on his arm, he swung me around and hit me with his arm. He hit me first with an open hand, then he hit me with his gun in the face."

The video shows Lopez's left arm extending toward Lawless' face, and then his right arm driving forcefully toward her, jamming the gun in her neck or jaw.

Internal Affairs investigators obtained the tapes a few days after the preliminary hearing. Shortly after that, Lopez was assigned to desk duty. Lopez, perhaps unwilling to perjure himself again, failed three times to appear at Lawless' trial. After the third time, the charges against her were dismissed. What prompted the prosecutors to keep the case alive that long is a mystery. Perhaps they didn't bother to review the tapes or to inquire about the progress of the Internal Affairs investigation.

The tapes would not have made it to the Internal Affairs investigators if Lopez and his friends had succeeded in their attempts to tamper with the evidence. After arresting Lawless, Lopez asked the store clerk to erase the security camera tapes, a request that was repeated by other officers who twice visited the store the next day. Those officers also asked the clerk to "help the cop out and testify for the cop." Remarkably, an Internal Affairs investigation found no misconduct on the part of those officers -- probably because their words weren't recorded.

Given the recordings of Lopez' aggressive behavior toward Lawless, however, the investigators were forced to conclude that Lawless was telling the truth. You might think that the unprovoked attack, the lies he told in his police report, and his perjury would have spelled the end of Lopez' career. Not so.

The District Attorney's Office reviewed the case and declined to prosecute Officer Lopez in December. Eight days later, he was reissued his weapon and returned to full duty.

Disciplinary charges against Lopez are pending. In the meantime, this hothead with a badge is carrying a gun in northeast Philadelphia.