Not all police are lazy ours are very good. I think the fact that you had no evidence i.e. your word against his was a factor in their lazy behaviour. I also have personal experience of being threatened with a machete, by my noisy next door neighbour. I went to the local police station and made a formal written complaint. Unfortunately I had no video or photographic evidence, just the word of my wife so the case would not have held up in court. However the local police chief paid him a visit and the noise has since stopped.