I'll put good money on it that the Jag driver would not try that sort of manouvre on a bigger bike. No matter what the small bike rider was doing, whether he was in the right, riding badly or whatever, the Jag driver should not have tried to over take on the exit of the roundabout. The outcome could have been quite tragic.
He should not have argued with the Jag driver and called the police to the incident, they could be the judge, not some jumped up arrogant driver who thinks he rules the road.

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