I think the email is a hoax.
That said, you concern yourself with legalisms too much. Even a Supreme Court Justice would pay attention upon being told that a certain decision would trigger riots where his safety, and the safety of everyone he cares about, could not be guaranteed.
Likewise, even a Supreme Court would realize that ruling Obama a non citizen would toss the country into chaos.
Why else would not the little zer0 have to produce proof of his birth place?