The eponymous Joe Darke, who the whole incident is focussed around
The SL-9 Incident (More commonly known as the 'Joe Darke Killings') was a series of mass murders in LA which culminated in the killing of the prosecutor Neil Marshall in the Police Station. It was also the trial 'State VS Darke' in which the the defendant was found guilty and was executed.
Warning:Spoilers follow
The early killings
The incident began when Darke accidently ran over and killed a man while driving his car. He then began to panic, and killed the eyewitness to the crash in a fit of paranoia. He then commited more murders on people who had stumbled onto the scene before escaping from the scene of his crimes.
In response to this, a team of detectives were set up by Detective Bruce Goodman, overseen by legendary detectives Damon Gant and Lana Skye. Other members of the team were Neil and Jake Marshall, Angel Starr and prosecutor Miles Edgeworth. Darke soon turned himself in and the matter seemed to be finished
The Murder of Neil Marshall
The main members of the investigation team. Neil Marshall (B.Left), Angel Starr (Left) Jake Marshall (Center) and Bruce Goodman (right)
However, on a stormy night not long afterwards, Darke escaped from the interrogation room of the police station where he was being questioned by Damon Gant and Neil Marshall and blindly ran into the joint office of Gant and Lana Skye. Ema Skye, Lana's younger sister was there, but before Darke could get to her he was attacked by Neil Marshall who had caught up with him. While it was too dark for Ema to see the faces of the two men, she saw that one of them was in control, holding a knife over the other. She assumed the figure was Darke, and she pushed the man to the floor, knocking over an unstable jar. However, it was actually Neil who she pushed.
After all three of the people lost conciousness, Gant entered the room. Seeing that he could use the situation to further his career and control the prosecution office, he cut out the piece of cloth from Marshall's jacket which had Ema's handprint on it; before impaling Marshall on his cerimonial suit of armour. He then took a picture of the suit of armour as insurance, and wrote Ema's name on one of the shards of the broken vase. He then put the section of jacket and the piece of jar in his safe.
Lana Skye then entered the room, and after looking at the crime scene assumed that Ema had accidently pushed Neil to his doom. Gant offered to 'cover up' the crime scene and she agreed. They moved the body and the unconcious Darke to the other side of the room, and planted the broken tip of Darke's sword into the murder wound to make it look like he'd killed the man. The plan succeeded, and the police arrested Darke again and charged him with murder of Neil Marshall.
The Trial and Aftermath
Miles Edgeworth was the prosecutor in charge of the trial against Darke, but he was concerned about the amount of evidence that was found. To that extent, Ema Skye was called as a witness to the crime. She tried to explain what had happened but she was too frightened to speak in court. She had drawn a picture to show what she saw on the back of the evidence list, but it had been torn in half by Gant, and the half that showed the unstable jar was hidden in Gant's safe. There was enough evidence to charge Darke for the murder, and he was found guity and sentenced to death.
Immediately after the trial, Gant was promoted to Chief of Police. He then moved Lana to the Prosecutors office and used the cover up to blackmail her into doing what he asked. The three detectives were suspicious of the verdict, so he fired Angel Starr and demoted Jake Marshall to a patrolman; although he kept Bruce Goodman at his post so his actions wouldn't be too suspicous
The trial also created rumours about Edgeworth falsifying evidence, rumours which didn't die down. While that wasn't true, there were also rumours about his methods that were true, as he did withold evidence and instruct witnesses to omit parts of their testimonies. Even two years later Starr, Marshall and Goodman still suspected foul play, and it was their actions that prompted Gant to deal with the problem in his own way.