Douglas Drakefield was a sex offender and child predator. He had multiple arrests for suspicious activity around children, but he had a good lawyer and was always released, having only been to prison once on a two year sentence of which he served 18 months.
During The Looking Glass, Mitchell is dragged into the police station and ordered to kill Drakefield by Chief Constable Wilson. Mitchell refuses, stating that he is not a killer, and leaves. Wilson persists, however, and sends Mitchell to Drakefield's house. Drakefield pleads for his life and Mitchell tells him to turn himself in, saying he'll be "safer in prison with 500 murderers than out here with one of me".