A.Viator: This is one argument………….
Human Rights Act 1998 Chapter 42 ARTICLE 5
RIGHT TO LIBERTY AND SECURITY
...
The victim of arrest or detention in contravention of the provisions of Article 5 of the Human Rights Act shall have an enforceable right to compensation, in this case, against the Captain.
As far as I am aware, there are currently no commercial UK airlines who owe any obligations to anyone under the Human Rights Act, and therefore none of their passengers have any right to compensation under that Act.
Golf Charlie Charlie: Several years ago (before 9/11, for what it's worth), I was diverted to Manchester from Heathrow on an inbound Qantas flight due to fog. I elected to travel to London by train, which they allowed me to do with no problem at all, but they made it clear I would not get my bag and that it would fly down to Heathrow later, with its collection my responsibility. In the event, for other reasons, this was no problem for me.
QF won't do this any more. (I also remember other airlines allowing this at MAN in the past after diversions from LON.)
A couple of years ago, I was diverted from SYD to MEL because of fog. Nobody with checked bags on board was allowed off at MEL, because there was no baggage handling capacity there for diverted aircraft. IIRC, there was one person allowed off because he only had cabin baggage, and after a substantial amount of negotiation three out of a family of four were allowed off on the condition that the father remained on board, flew to SYD with the bags and then flew all the bags back to MEL on a domestic. Me, I wanted to get off and get on the MEL-WLG flight that was at the next gate instead of going on to SYD and taking my chances with the SYD-WLG flight I was booked on, or subsequent flights - no go. But I made my booked SYD-WLG flight because it too had been delayed sufficiently.