On Wednesday, a Philadelphia Common Pleas Court jury began hearing evidence involving the Oct. 16, 2009, incident that left the 31-year-old Koons in a coma for two weeks until he died.
Left bruised and battered - but alive - was Koons' friend George Foreacre III, 38, who went with Koons to the Oasis to watch a Phillies playoff with the Los Angeles Dodgers.
Assistant District Attorney Michael Barry told the jury of eight women and four men that the evidence will show that Pettit, 51, is guilty of third-degree murder in Koons' death.
During the evening confrontation in the Oasis parking lot at 6800 Essington Ave., Barry said, Pettit punched Koons in the forehead so hard he cracked Koons' skull and drove bone a quarter-inch into the brain.
Koons fell back and hit his head on the asphalt, fracturing the base of his skull and causing brain damage that eventually killed him on Nov. 2, 2009.
"Working bouncers are not allowed to do whatever they want to do to anybody in the bar," Barry said in his opening statement. "That's a misconception held mostly by bouncers."
Defense lawyer Robert Lynch asked the jury to not second-guess Pettit over events that occurred in seconds.
"Mr. Pettit and the others were all doing their job, doing what they were supposed to do to stop two drunk males and their aggressive behavior," Lynch said.
Lynch said the Delaware County men were loud and abusive to patrons and employees when the Oasis bouncers ejected them into the parking lot about 6 p.m.
Barry, however, said there were no complaints from other patrons, and Foreacre has testified that Koons' only verbal confrontation was with Laflar's girlfriend, a club employee. Laflar's girlfriend was also the former roommate of Koons' former girlfriend, a club employee and mother of Koons' two children.
Originally, five men were charged in the incident.
Laflar and Pettit, the club's manager, were ordered to stand trial on a charge of third-degree murder. Three Oasis bouncers - Edwin Padua, 52, Timothy Carpenter, 32, and Brendan Davis, 35 - were charged with assaulting Foreacre.
But Laflar, 46, died of a drug overdose in January, 11 months after federal investigators subpoenaed records of two of his strip clubs and an auto salvage shop in a grand jury probe of kickbacks and payoffs involving the Philadelphia Police Department and the Department of Licenses and Inspections.
On Tuesday, Padua, Carpenter, and Davis decided to be tried without a jury by Common Pleas Court Judge Jeffrey P. Minehart. After a day of testimony, Minehart acquitted the three.
Contact Joseph A. Slobodzian at 215-854-2985, firstname.lastname@example.org, or @joeslobo on Twitter.