Why does Patrick's lawyer act funny, as if he were joking, when Patrick was confessing to him at the bar?
In this question I get an answer
In the end, Bateman seemingly kills dozens of police officers, something that would not easily be forgiven, forgotten, nor without being the talk of the town and also among his socialite 'friends'. Even his 'confession' is aluded to by his lawyer as a laugh as they believe Bateman is too reserved to commit such acts.
Which explains why the lawyer acted the way he did, but not really because he was calling Patrick, "Davis" and said that "Bateman was dull" (something to that effect).
So what's the deal with the lawyer? Did I just misunderstand the conversation?