Is enticing someone to suicide illegal?

According to this story, a man has been arrested for allegedly trying to lure up to thrity-one women (some bringing their children along!) to his home where they would have sex with him and then kill themselves. He wasn’t successful (they think), and he’s being tried with solicitation to comitt murder and possibly attempted manslaughter.

Now, I’m not defending the guy. At best, he was taking advantage of women who were depressed and borderline suicidal to begin with to fulfill his rather disturbing fetish. And God only knows what would have happened to those kids. He is certainly diserving of his own pitting, but that’s not why I’m here right now.

What exactly did he do that was illegal? Assuming for the moment that these women were sane and competent in the legal sense, what crime is comitted by asking someone to kill themself in front of you? He wasn’t coercing them. He wasn’t a mental health professional and wasn’t posing as one. It wouldn’t even necessarily be assiting suicide, as he need not do anything but watch them do it. It’s sick and it’s wrong, but has this guy discovered a perfect crime so bizarre that it’s not covered by any real law?

Suicide is a crime in most, if not all, states. Wouldn’t this guy be guilty of conspiracy if he helps to organize a crime?

I haven’t seen it, but I think this is the entire plot of the movie “Saw”. At least the teaser / DVD comercial goes out of its way to imply that the mastermind of the murders “drives his victims to commit suicide”.

I assume that this question has to be addressed near the climax, or end of the movie.