HE was drunk and he's a squaddie - my brother was a squaddie and he had squaddie mates and i know that when they get drinking they are leery as fuck.
we cannot hear what is being said on the video but given the fact that he's stood 8-10 feet away he's probably gobbing off to the coppers and he's keeping his distance to try and get a head start on the inevitable chase, but he's so pissed that he falls over.
i have no sympathy for the squaddie, my brother recived a similar beating from police - the cops have a hard job and were probably getting shit all night, the squaddie just copped for it all.