This police officer had been in the force for many years now and had seen many things. What he saw on this particular day was something he just could not stand. He was a good officer and always went out of his way to ensure that he did the right thing by everyone.

 bbc.co.uk 

Being a policeman is hard work, at the best of times. It often involves having to make difficult judgement calls. When this officer saw what a woman driving in front of him was up to, he knew that he had to somehow intervene.