Akatsuki would take this fairly easily for me. Joker's no Batman and I doubt he could stop someone like Itachi, who had reactions well beyond Batman or Pein, who could take all of Gotham out in one blast if he needed to. Plus with his gravity manipulation powers, I don't think Joker could do anything against him.
Joker usually takes advantage of Batman's not willing to kill. Akatsuki would have no qualm about killing him and at the end of the day Joker's only human.
















