In reading through section 930 of the Federal code,
(note: Section 930 is way down at the bottom) there is this glaring exception:
Sec. 930. Possession of firearms and dangerous weapons in Federal
(a) Except as provided in subsection (d), whoever knowingly
possesses or causes to be present a firearm or other dangerous
weapon in a Federal facility (other than a Federal court facility),
or attempts to do so, shall be fined under this title or imprisoned
not more than 1 year, or both.
(d) Subsection (a) shall not apply to -
(3) the lawful carrying of firearms or other dangerous weapons
in a Federal facility incident to hunting or other lawful
So I am kind of curious as to how cases of civilians going before a Federal magistrate were adjudicated.
I could keep quoting, but it would take all day. Check the link and see for yourself. But, the way this reads, for regular federal facilities, and for federal courts (subsection e),
no person shall be convicted of an offense under
subsection (a) or (e) with respect to a Federal facility if such
notice is not so posted at such facility, unless such person had
actual notice of subsection (a) or (e), as the case may be.
So, notice is required, either via signage or verifiable notification.
Even then, it appears that regular federal facilities (everything other than courts) are not supposed to restrict possession of weapons for "other lawful purposes."
I'm no lawyer, but it seems the government would fight an ultimately losing battle on this type of case; OTOH, I certainly don't wish to be the test case, and lose my shirt on legal costs, appeals, etc.