No longer mentally ill, according to boffins.

Jimmy Savile was questioned by police over crimes Sutcliffe was eventually convicted of, and the two of them were mates: http://www.mirror.co.uk/news/uk-news/jimmy-savile-yorkshire-ripper-suspect-1420344

Look, here's Savile watching on as Sutcliffe enjoys a Masonic handshake with Frank Bruno:
http://i.dailymail.co.uk/i/pix/2012/11/11/article-2231263-15E47C0B000005DC-524_634x369.jpg

It's a funny old world.