The Black Diaries are diaries purported to have been written by the Irish revolutionary Roger Casement, which contained accounts of homosexual liaisons with young men. They cover the years 1903, 1910 and 1911 (two) and were handed in to Scotland Yard after his capture in April 1916.
Casement was charged with treason following the Easter Rising. During his trial the prosecution (F. E. Smith) suggested to the defence barrister (A. M. Sullivan) that they should jointly produce the diaries in evidence, as this would most likely cause the court to find Casement "guilty but insane", and save his life.[1] Casement refused, and was found guilty and condemned to death.
The British government then began to circulate photographic page copies to block any appeals or requests for clemency, particularly from the US, that showed his "sexual degeneracy".[2] The effect of their circulation was to dissuade some would-be supporters from joining an appeal for clemency, and Casement was hanged on 3 August 1916.[3]