The Pilot-In-Command of any aircraft used to have the legal right to refuse armed intervention during a hijacking.
Prior to 9/11, the Captain of any aircraft you flew in was legally empowered to refuse any and all armed intervention during the course of a hijacking. The rational was that the Captain knows what's going on inside the plane better than those outside the plane.
This was illustrated in the hijacking of 58 November Oct 4, 1971. The Captain warned the armed agents outside the plane that they were endangering lives by using forceful tactics. The agents refused to listen and opened fire on the craft. The hijacker killed everyone on board once the agents opened fire.
This was the first time the FBI and J Edgar Hoover lost a wrongful death action in Fed Court (Downs vs USA 522 F.d2 990).
Since 9/11 the law enforcement community has removed the legal rights of a captain to hold off action if they desire. The idea that pilots of aircraft can't be trusted to convey accurate information is part of today's law enforcement argument. In other words, only the law enforcement agents undertand everything going on with the plane, and pilots should not be a factor. Only the judgement of the agents on the ground will be considered.
However this is not supported with any evidence in any type of hijacking. There are no cases where the decision making of the pilots caused the innocent loss of life.
I think the pilots should be in command during these scenarios until they ask for help from the outside.
I am now trying to bring law enforcement together with aviation professionals together to debate these issues. The pilots are due, and the public too.