here is 2008 Article about Harriet Harperson and the links betwen PIE and the the NCCL in the 1970's
http://www.telegraph.co.uk/news/politics/labour/4949555/Harriet-Harman-under-attack-over-bid-to-water-down-child-pornography-law.html
The activities of the organisation she worked and its affiate, PIE, for could have made some of what Jimmy Savile and Garry Glitter did with under-age children to be legal.