Of course, if you do select tenants, in part, by occupation, eventually there will be a lawyer ...
I agree - which is why I say don't do it. :)

After re-reading Jonathan Roth's post, I see he was referring specifically to California.
(And they do have a law against discriminating based on "source of income")

So if you're in CA, both would be illegal discrimination - one illegal under state law, the other illegal under state & fed law.