In 2020, James Watts, a probationary constable with West Mercia Police, posted a series of offensive memes to a WhatsApp chat group that included several of his former colleagues at HMP Rye Hill, where Watts had served as a prison guard. One meme showed a prayer mat printed with the face of George Floyd, murdered by the Minneapolis police officer Derek Chauvin. Another featured a white dog in a Ku Klux Klan costume. Watts received a twenty-week prison sentence and a lifetime ban from holding any policing role. The ruling has proved controversial. The conservative journalist Ed West has questioned the severity of Watts’s sentence in the light of another recent case, in which two Blackburn men were spared jail after launching an unprovoked attack on a man that left him in intensive care. In West’s view, the British justice system comes down harder on offensive speech than on acts of physical violence. The Communications Act 2003 makes it a crime to post anything ‘grossly offensive’ on a ‘communications network’. Could Watts’s prosecution be justified when his messages, however deplorable, were intended only for specially invited members of a chat group? Don’t we all say things we shouldn’t when we think no one beyond our in-group is listening? Should the law intrude that far into our private lives?

The historian Tiffany Jenkins thinks not. The right to speak freely – and, indeed, to be a reprehensible bigot – in private ‘is important, and its loss undermines autonomy and freedom’. In Strangers and Intimates, her history of the idea of privacy from ancient times to the present day, Jenkins attributes the ‘contemporary drive to eliminate controversial or anti-social opinions and speech from the private realm’ to a more general blurring of the boundary between our public and private lives. She dates the  public–private distinction to the period following the Reformation. ‘Medieval Catholicism’, she writes, ‘was collective and communal.’ God was omnipresent (‘Can any hide himself in secret places that I shall not see him?’ God asks in the Book of Jeremiah). Church bells rang out to summon the community to prayer. Collective worship and private acts of piety alike fell under the aegis of the all-powerful, all-seeing Church authorities. By proposing a direct, personal relationship between man and God, bypassing the intermediaries of the religious establishment, Martin Luther encouraged a ‘sense of the individual conscience’ that would ‘become the cornerstone of private life’. In England, by enforcing assent to the break with Rome, the Reformation gave rise to a division between public display and private belief. On 4 May 1535, three Carthusian priors were hanged, drawn and quartered at Tyburn for refusing to take Henry VIII’s Oath of Supremacy. Surviving colleagues at the London Charterhouse were more circumspect, publicly acknowledging Henry as supreme head of the Church of England, though not before beseeching God ‘to pardon thy servants for the sin which, though heart and conscience resist, we are about to commit with our lips’.

Jenkins sees the emergence of the modern trading state in the 18th century as a milestone in the separation of public and private. The growth of international trade created a culture of information exchange centred on new public spaces. The Jamaican Coffee-House in St Michael’s Alley off Cornhill was where