British Labour peer Lord Longford has died aged 95.
The peer died at London's Chelsea and Westminster Hospital.
Lord Longford campaigned for the release of Moors Murderer Myra Hindley.
The prison reformer, whose full name was Francis Aungier Pakenham, was the seventh earl to hold the title.
Chelsea and Westminster Hospital spokesman Mr Mark Purcell gave a statement on behalf of Lord Longford's family.
It said: "Lady Longford and the family announce with deep sadness the death of Frank Pakenham, Earl of Longford, at the age of 95. It was a great life and he was a great man."
In 1931 he married Elizabeth Harman, a prolific writer, and together they had eight children. But the couple were struck by tragedy when their daughter Catherine was killed in a car crash aged 23.
Lord Longford was made a Knight of the Garter in 1972, the same year that his controversial Pornography Report was published. The report challenged the view of the permissive society that pornography did no harm and earned him the unwanted label Lord Porn.
But by far his most controversial campaign was his persistent call for parole for Hindley. He spoke out vehemently year after year especially in 1985 when the Parole Board refused to release her after 20 years for at least another five years.