Pointedly Roy Jenkins agenda of social liberalisation was cross-partisan. And Tony Blair's part of his rejection of Labour's heritage as working class paternalist party.
Labour is neither SocDem or Big-tent Liberal, its left-inflected British nationalist.
Borners
"labour is a socially liberal party" factoid actualy just statistical error. average labour cabinet minister is 0% liberal. bisexual roy, who does not live in a cave & wants people to have over 10,000 civil liberties, is an outlier adn should not have been counted