asdf wrote:

How could they be forced to? It's a chicken and egg situation; under
the current system, the only pratical way the public can "force"
Labour to do anything is to (threaten to) elect the Tories, and vice
versa, and neither party will introduce PR or STV.

Whilst a large Lib Dem opinion poll lead might do the trick, enough of
the electorate is firmly stuck in a 2-party (or 1-party) mindset for
this to remain pure fantasy.

Labour is considering holding a referendum on switching to Alternative Vote
on election day.