Supposed you have 3 different personalities. Does that mean you are counted as 3 people?

By law, how many are there of you?

If only 1, then how come you're not responsible for the crime your "other" personalities did?

Your counted as one person and you if you have multiple personalities your usually not responsible for what did while you were not lucid / were insane. Ofcourse your still responsible for for your actions while lucid - not taking medication, not seeking medical help, knowledge of what you have been doing will all count aganist you when factoring in if you commited a crime.

Actually multiple personality disorder is widely considered fake by most psychologists.

With the few "cases" of it recorded actually being from therapists inadvertantly training their patients to seperate those people into "different personalities"

I'm bi-polar, but that's not the same thing.

but... anyone can have multiple personalities look at spider man 3 :D

His personalities being emo, douchebag and tosser. Or was that SM2? I can't keep up with these shitty movies.