Undetected by his colleagues, his sexual deviancy had manifested itself first in flashing and voyeurism. It then escalated into sexual beatings, rape and finally, when in the full grip of paranoid schizophrenia, into killing. As Detective Superintendent Michael Banks said: "Each time he got more and more violent."
His diaries contained references that were classic signs of schizophrenia— fears that his food was being spiked, that people were talking about him behind his back and how women offered "instant sunshine" but were only out to exploit him.