Actually, I have studied about Dahmer quite a bit, and honestly from what I've studied of him more in detail (other than the apparent gruesomeness of the crimes) it really wouldn't surprise me if he had AS or Schizoid PD (two very similar disorders).
From what I have found in the very least-- aside from AS-- Dahmer doesn't fit the picture of Psychopathy. He wanted to be with his victims and most of his murders were about him not being able to fathom the idea of letting them go. He wanted relationships with these men, but he didn't understand how to get that and communicate that to them. Yes, he could lie. So can I. But nevertheless, his crimes weren't motivated to cause these men harm but to keep them with him ALWAYS. He knew so little of how to be with other people that he found it easier to even be with them when they were dead.
Dahmer seemed to have also an extreme interest in anatomy and learning through dissection when he was young. He dissected many animals. He didn't kill them first and then dissect them. He would instead collect roadkill and perform experiments. This was a childhood passtime of his, the little experimenter. And he was also very good at chemistry; his father being a chemist I believe as well.
His first murder was when he was just 18, and he invited a guy over to his house (no one else was home) and they hung out together. But then, after a couple hours, the guy wanted to leave. Dahmer got scared and desperately didn't want him to. In a split second, while the guy was trying to leave, Dahmer hit him with a dumbell. This was in no way a planned murder.
His second murder was accidental and he didn't even realize he had done it.
In short, at his trial, Dahmer wanted to be punished for what he had done. Psychopaths would generally deny until they went blue in the face.
It seems that Dahmer killed out of loneliness and the inability to interact and communicate with living people. Not out of a need of sadistic satisfaction. True, his actions would win him the diagnosis of Antisocial Personality Disorder, but this disorder is based solely on behavior and actions and not the underlying cognitive functions. Psychopathy as a separate disorder (not listed in the DSM) is different in that it is a reflection of those cognitions. Dahmer does not fulfill these criteria for Psychopathy.
So, I lean either towards Aspergers or a variation of Schizoid Personality Disorder or something similar.
Again, too difficult to give a psychological diagnosis to an individual postmortem.
But my question is: Do the people on this forum who have passed off at this possible diagnosis of Dahmer as Aspergers do this because they don't believe he had it, or they don't WANT to believe he had it because it would paint Aspergers in a more negative light???