[He doesn't have a death price. It's a valuable piece of information, it makes the experiment not a total loss, that the eye application could at least stave off that much. He rolls his eyes, it's obvious he thinks John is just trying to deflect.]

You must have argued recently.

[His voice turns more musing, working things out bit by bit.]

Unlikely to be over food or other supplies. Either he has done something you consider reprehensible, or you have done something he considers so. You will bend on most things, it's a habit left over from childhood to placate a situation and try to, fruitlessly, appease everyone around you. So it's something even you won't bend on. He has killed someone-- No, that makes no sense, he isn't a senseless murderer. Gang leader, perhaps; psychopath, no. There aren't many people here deserving of being killed so--

[Of course, it's been staring him in the face. Hadn't they just had the Joker in their custody? The one person most people want to see gone, and someone both Alfie and John have a hatred for thanks to the woman dead before he got here. Finley, or something like that.]

He wanted you to kill the Joker. Revenge killings aren't really your style, John.