" @The Enigma said:

" There is no doubt that Joker is insane, but I do believe that he overplays his insanity so as to create a justification for his actions (and avoid death). "

Isn't that what Dick said once? I remember reading something where Dick was like "I think you just fake your insanity because if you weren't you'd be responsible for your actions" (<--- not right quote!) and Joker was all "STFU!"  But no that guy's crazy. "

Heres an extract from the collector's edition of Batman:AA , patient notes about Joker...
 
The Joker
Real Name: Unknown
 
Psychological Profile 
My most challenging patient at Arkham. the Joker's derangement defies easy classification. His rapidly changing mood swings hint at borderline personality disorder, but he has no trace of associated identity problems. He also displays signs of deep narcissism , but nonetheless he has a well-developed sense of others, as his ability to manipulate everyone from orderlies to doctors in Arkham is extraordinarily well-developed, he also shows all the signs of a highly functioning sufferer of antisocial personality disorder. At times I almost wonder if he is actually insane at all.(this underlined  part is highlighted with a marker pen)
 
Additional Notes
His criminal record makes it clear that he is an unrepentant homicidal maniac.
 
He is extremely manipulative, the file detailing Harley Quinn's associations with him is fascinating reading. Its unfortunate I was not on staff at the time to witness his seduction of her firsthand.
 
His past is unknown, and his answers to my questions about it are wildly inconsistent and frequently fantastical 
 
Dr. Penelope Young
 
 
I feel I need to add this little note from Harley's profile too...
The excessive and invasive psychological screening I had to undergo here at Arkham was largely due to her earlier fall from grace. At times I'm resentful of this; the mere idea that I would become inappropriately involved with the Joker or any other inmate is preposterous.
 
 If you've played Arkham Asylum then Dr. Penelope Young may be a familiar name...
 
 
Basically, yeah he's definitely insane, but he has a lot more control over his insanity than most, maybe even completely. He does seem to enjoy his own persona.
 
As for those saying he does it to avoid jail or a death sentence. This simply cannot be true, as there was a story where he was accused of several murders (which he actually didn't commit amazingly) and he pleaded not guilty, since the murders were amateurish (his words). This gave the authorities the work-around to have him put to death because of his plea. Then, Batman being the incorruptible chap that he is, goes on to catch the real killer and gets the Joker released. Its possible he did this because he knew Bats would get him out, but Bats was the one that "caught" him over these same murders in the first place so I consider it unlikely.

Is the Pope Catholic?

" "Insane" is a subjective term.  "

The Joker's not insane.
Apparently he managed to play it straight for a while recently.

he is super sane 
his sanity is continually reevaluating and changing itself for every situation 

Joker's so insane that people question his insanity.

LOL at the view to post ratio.

anyone who frequently dresses in purple and green suits can't possibly be considered sane.

He's Super-Sane.

"

DarcStorm said:

Deadpool, Joker, Green Goblin, and DarcStorm are the most insane people ever.

Yes, those guys are insane also. I want a comic with Joker and Deadpool together just talking about anything, and breaking the 4th wall.. LOL "

"

Of Course, he's not 'sane' like everyone else, but he's not 'insane,' either. He is 'super-sane' able to place himself objectively in whatever situation with the mindset of taking whatever role is most adventageous to his master plans.

"

Call him Insane s stop the Joker and explain what he is. 
He is Pure Chaos, the representation that Random acts of injustice in the universe show that there is no justice in the universe for the same every system and goverment is a lie, the only way that thing have sense is in chaos.

I think the joker is completely insane.

"The joker just needs a hug " 

The Joker is not insane, if you believe such then you were just fooled by one of the oldest tricks in the book. Malingering has been used as far back as Odysseus in the Odyssey.

Insane people do not hire expensive legal teams to make sure their insanity defense works. If the Joker is as insane as you think he is then the facts should speak for themselves and he would need no lawyers. The Joker's insanity defense is the perfect counter to the Bat's incorruptibility.

Joker is a complete nutter.

He's functionally insane.... Meaning that IF HE wanted to he could manage to be good if he truly wanted to be but his insanity has never really been in question. I'm pretty sure that Robin quote about him faking came from the cartoon but either way Robin knows that questioning Jokers insanity would um drive Joker insane since Joker gets such a kick out of it.

He is truly insane and that is what makes him great and the perfect villain for Batman.

I think he is in too complete control of himself to be insane.

Well in the real world he wouldn't be headed to Arkham Asylum everytime he gets locked up, he'd head straight to an electric chair. Typically for a successful insanity plea the guilty person has to be unable to tell the difference between right and wrong, Joker knows that what he's doing is wrong but he just doesn't care. So he's obviously not sane like most of us here, but I don't think that would save him from the death penalty, or at least life in a regular prison.

how old is this thread?