APD seem to be doing a good job of keeping the lid on.
Thus far, no one has died, hopefully, the APD will not let the situation escalate to killing the guy without exhausting all avenues. 
The courts can redress any perceived improprieties on the part of the police, but only after the fact, and only if one survives the encounter . . . : )
The guy has a right to his firearms and to use them self-defense.  Any law abiding rights issue ended when he unlawfully threatened the workers with his weapon, and certainly when he shot and injured the two police officers.
APD is now dealing with the violation of the public peace.