Damian McBride’s revelations about back-stabbing in Gordon’s imperial court raise a serious question: what was in it for him? The Roman delator (‘informer’) was not some little squirt from central casting, but a man on the up with an eye on power.

The model delator, as the historian Tacitus describes him, was one Hispo, who, ‘poor, obscure, impatient, creeping to the emperor’s cruel nature by his secret accusations, spelled danger to anyone of eminence, and won power from the emperor, but hatred from everyone else.