D. H. Lawrence finished Lady Chatterley’s Lover in 1928, two years before his death, and had it printed privately in Florence. It tells the story of Constance Chatterley, married to a rich mine owner paralyzed in the First World War, and her love affair with the gamekeeper on his estate, Oliver Mellors. It is also an angry book about class, industry and the deadening of modern life. But what made it notorious was that it described sex frankly and used words that could not then be printed in Britain. For more than thirty years, only expurgated versions were legally sold there.

In 1959 Britain passed a new Obscene Publications Act, which allowed a defense that a book’s literary merit served “the public good.” Penguin Books decided to test it. In 1960, for the thirtieth anniversary of Lawrence’s death, it printed 200,000 copies of the complete novel and was charged with obscenity.

The trial opened at the Old Bailey in London on October 20, 1960. The prosecutor, Mervyn Griffith-Jones, asked the jury of nine men and three women: “Is it a book that you would even wish your wife or your servants to read?” To many people even then, the question sounded out of date. Penguin’s lawyers called thirty-five witnesses, among them the novelist E. M. Forster, the critic Rebecca West, the scholar Richard Hoggart and a bishop, all of whom argued that the book was a serious work of literature.

On November 2, after about three hours, the jury returned its verdict: not guilty. Penguin’s paperback sold out at once, and some three million copies were sold in the months that followed. When the publisher reprinted it, it added a dedication to the twelve jurors.

The trial is often remembered as the moment Britain’s old censorship cracked. Within a few years the theatre censor was abolished and other bans fell away. The poet Philip Larkin turned it into a joke about his own generation, writing that sexual intercourse began in 1963, “between the end of the Chatterley ban / And the Beatles’ first LP.”