I agree with Ana that he violated the law he was charged to enforce. Then again, recent revelations establish that Spitzer has been whore-mongering for quite some time, and has managed to be an effective public servant in spite of it. I wish I could say the same about the Bush League.
And I do condemn his hypocrisy, not just for violating the law he enforced against others but for seeing the stupidity of such laws and doing nothing to change them. It appears that Spitzer suffers from an elitist belief that he and his class need not obey the rules, but the rest of us are not so entitled. I can say the same about the Bush League.
And his difficulties have been cheered by the Republicans, the Wall Street types who brought us the mortgage crisis, and other organized criminals. No sane person wants to gets on board with that ilk.
Ultimately, I believe that Spitzer should stay because of the direction in which his resignation will push future governors and other politicians. Either we will be left with nothing but sanctimonious tight-asses who actually believe in laws that regulate private morality, or political hypocrites who understand the futility of such laws, but do nothing to reform them as ordinary human beings suffer the consequences.