Mafia 61. Star Wars: Classic Trilogy

The clues are there, but I can't figure out who the killer is.

It's a serial killer. First, the mercenaries are mentioned. Second, they killed the Sith, which means Vader, who was already a Mafia member for a couple of days. She herself pointed this out in the question about my Mafia affiliation. O_o

In short, if the Mafia hasn't shot at the serial killer even once, but instead systematically hindered Tarkin, then we don't have many chances. BUT
Then we need to find the Mafia now, hang him, pray that Jabba doesn't have enough power for a triple shot, and then hope that he doesn't kill Tarkin, but instead, Tarkin manages to shoot the serial killer. Then the town wins. But there are many "ifs" here.
I don't know how the Mafia can win now, which means that Leia, who is still alive, will almost certainly hinder the town at the end. Perhaps not with a shot, but again, with sabotage. Therefore, it's better to identify her somehow now.