He did not side with police, he just didnt like the bougie people joining the cause treating it like a trendy counter culture. To paint the picture a little better, in “The Road to Wigan Pier” Orwell said the following:

One sometimes gets the impression that the mere words ‘Socialism’ and ‘Communism’ draw towards them with magnetic force every fruit-juice drinker, nudist, sandal-wearer, sex-maniac, Quaker, ‘Nature Cure’ quack, pacifist, and feminist in England.