Marx opposed state press censorship throughout his life although he didn't write much about it after he was indicted on several counts related to his writing and editorship of *Neue Rheinische Zeitung* in 1848-49. And by that time he was not defender of press freedom per se, but a proponent (as speech to the court in one of his trials indicates) a proponent of a miltitant press that would expose injustice and destroy the existing order. Later, he wrote a bit about bourgeois press distortions of the working class, and, in a couple of reports to the First International, of efforts to prohibit working class press freedoms.
btw: despite his dislike of religion, 'late' M writes in _Critique of the Gotha Programme that 'everyone should be able to attend to his religious as well as his bodily needs without the police sticking their noses in' even as he points out that the workers' party role is 'liberate the conscience from the witchery of religion.' Michael Hoover