Flags at half-staff

My understanding is that only the President or Congress can order The U.S. Flag to half-staff and that absent presidential or congressional permission, governors can have state flags go to half-staff while Old Glory stays at full-staff. Yesterday, Colorado Gov. Ritter ordered flags to half-staff to honor 2 servicemen killed in the line of duty.

First question: is it correct that this order was incorrectly (or even illegally) given?
Second question: if so andI refuse to obey the order, where in the USC would it state that the Governor cannot order the Federal flag to half-staff?
Third question: IIRC, the MIA/POW (black) flag is never to be flown at half-staff but instead is not flown when the U.S. Flag is at half-staff. Is that true and is it in the USC?

Sometimes in DC there are some Federal buildings with half-staff flags and others without. I was trying to find some resource for knowing who died and warranted it, but I failed, so I just concluded that the flags just got stuck or nobody bothered to change it or something.

Perhaps the governor ordered the flags to be flown at half-mast only on state buildings, over which he has authority?

I would imagine only the POTUS has authority to order flags at half-mast on Federal buildings.

Or did he make the order for all government buildings?

Anyone can order half-staff on any flagpoles over which they have authority. You could fly the flag at half on the flagpole in your front yard to mourn the death of your great-uncle, and still be within the Flag Code.

Chronos is right:

At college, the flag would sometimes be put at half-staff because someone on the board of trustees had died. It obviously was a decision at a much lower level than president, congress, or governor. It was the only flag at half-staff in the city.

The flag code is a guide intended to describe proper handling and display of the flag. I like the summary at USFlag.org : ‘No disrespect should be shown to the Flag of the United States of America’

The section detailing flying the flag at half-staff includes:

The code details that governors can proclaim that the flag be shown at half-staff. Even if it wasn’t explicitly declared, the ‘recognized customs or practices’ clause covers it. Even if it didn’t at worst misdisplay is disrespect of the flag, but not illegal.

And on preview I see the many excellent points that the command decision rests with who has authority. All the code ‘requires’ is respectful treatment.

Confirming what Chronos said, my husband works at a hospital and it’s his call whenever the flags need to fly at half-staff.

link

I worked in a state facility (in New York). We would get a direction from Albany telling us to fly the “flags” at half-staff. So we would fly both the American flag and the state flag at half-staff.

As to the POW/MIA flag, the code that applies (36 USC 902) just says that this flag is to be displayed, when it is, in a manner that is “visible to the public”, otherwise it seems the the same provisions for display together with the US flag apply as would with any other flag or ensign. So it may be a practical consideration. Apparently nothing would keep me from adding a third flagpole to my building and flying the POW/MIA flag on its own right, full or half staff depending on the circumstances, save for tradition (probably arising from how the most common federal installation - Post Offices - usually have only the one flagpole for the US colors, so on the days that federal agencies are mandated to display the POW/MIA flag, that’s where it goes and where most Americans first saw it as an officially-sanctioned display)