Having spent a considerable time in my previous career dealing professionaly with the police I have to say that what happened here does not surprise me at all.
Recruiting standards have been lowered significantly over the years (And, no, I am not harping back to the halcyon days of graduate recruitment, which was abolished for elitism by the then home secretary).
Simply observing that the average bobby is pretty thick and when it comes to an intelligent assessment of a situation with which he is not familiar like nicking speeding motorists or dealing with a drunk then it is not surprising that plod comes up with a view which offends any rational or intelligent assessment.
Howl me down as you will, but by and large, intelligence is not a commodity conspicuous by its over supply in the ranks and the individual concerned will undoubtedly have been acting out of political correctness and to protect his own backside both of which he is well programmed for.
This is an absolutely apalling episode which detracts from safety because it increases the chance of someone commiting to a fatal landing when they should have gone around. Its as simple as that.