Prestige films such as The Blue Lamp were augmented by the long-running Scotland Yard series, which also highlighted the function of the policeman as paternalist authority figure.
But by the end of the 1950s, with society fragmenting, cinema would rapidly lose faith in the essential incorruptibility of British institutions. The mood was assisted by the liberalisation of censorship after John Trevelyan became the British Board of Film Censors secretary in 1958.
By the mid-1960s, the benign authority figure was fast vanishing from British cinema, along with the B-film crime drama…
(…)By … 1971, the police have practically vanished as agents of moral retribution, but it was Sidney Lumet’s 1972 masterpiece The Offence that really nailed the Blue Lamp myth. As with the earlier film, The Offence focuses on a veteran police officer, but here Sean Connery’s Det Sgt Johnson is visibly crumbling under the weight of maintaining his stoic mask.