'William James Chidley (1860–1916), a ground-breaking Australian sex reformer, has been the subject of a considerable literature. When he came to public attention via his public lectures on a ‘kinder’ mode of sexual intercourse, and police attempts to silence him failed, the New South Wales (NSW) authorities brought about a series of confinements to mental asylums, supposedly to protect the public from Chidley’s obscenities. He died at Callan Park asylum in December 1916. But an attempt was made to discredit Chidley even in death, with a medical officer claiming that the post-mortem showed that he had syphilis. This article examines previously undiscovered material on Chidley’s medical examination from his first admission to the Callan Park asylum in August 1912 which strongly suggests that Chidley did not have syphilis then and could not have contracted it later. The Chidley affair signalled the development of a new, but short-lived, ‘political’ phenomenon in NSW: the willing intervention of asylums to protect the community from ideas which governments considered harmful, where the existing laws had little purchase. Continuing public discontent with asylum policies was to be a major factor in the calling of a Royal Commission into lunacy in 1923.' (Publication abstract)