How the pendulum swung from the police not pursuing guilty Savile to pursuing innocent Proctor – and the disaster of Operation Midland.
That there may be as many as three investigations into Saturday’s events on Clapham Common tells us much we need to know.
An important new report by the Chief Inspector of Constabulary concludes victims have been let down for far too long.
She has pared the Home Office back to dealing what she regards as essentials: security policy, border control, policy formation.