bjcc I don't know what thread or what discussion your are contributing to, or whether or not you have read what this discussion has been about, but you say that
You ask who's in charge. The senior Police Officer on scene is. Police being the designated authority for terrorist incidents.
This is to do two things. (1) Ask a key question and give an answer, and (2) introduce a red herring - or, worse, to designate a bomb warning to be something that it has not been in the past (this is all about two specific events, not a bit of theory).
In respect of (1) your claim that it is the senior Police Officer who is in charge is disputed (as you assert it above) - no matter how firmly you assert it, and in respect of (2) you are apparently claiming that once a bomb warning is issued there is a "terroritst incident" and the aircraft commander loses all his or her responsibilities for the safety of the passengers. (It also looks like, if I many say so, that you have had some exposure to U.S. thinking on the widespread powers that the police seem to feel they can assume just by announcing the word "terrorist").
One way or another, the commander of an aircraft is legal in charge until some point. The purpose of ascertaining who is in charge of the aircraft and of the safety of the passengers is what this thread is about. You can state your version as firmly as you want, but I am clear in my mind that the facts in how these two flights were managed do not stack up. There is a manifest lack of clarity about policy and decision-making autonomy that needs to be sorted out.
I am not in the slightest interested in getting into a spat with you about terrorist stuff. This was a bomb warning, considered serious enough to lead to a directed diversion to an diversionary airfield - but
not considered serious enough to evacuate the aircraft. This is the key point of tension. In addition you are among a small number of individuals who seem obsessed with the rights of the police, but not of passengers and crew.
The issue for you to address is this: at what
precise point from the issuing of a bomb warning to the crew of an aircraft to the successful disembarkation of the passengers and crew does the responsibility for the disposition of the flight move from the captain to "senior police officer on scene". That, and the relevant policy, is what the letter from the Minister is about. It is not an unreasonable idea, to put it mildly, that these matters should be cleared up. An answer requires a bit more than a mere assertion from you which flies in direct contradiction of the law as it relates to the operation of aircraft. The real issue is the lack of clarity and the consequent potential for a really serious error of judgment.