Pfft!
I reckon that copper's got a difficult decision ahead of him. Either a) tell his superiors that he just looks that way under stress or b) admit he was gurning for the camera and possibly earn a bollocking for clowning around in the middle of a stand off.
(
Colonel Boris "...a desperate Buzzfeed imitation...",
Sat 10 Jul 2010, 0:17,
archived)