First, a disagreement. Your base assumption that police activity should scale linearly with population. This is just obviously not correct. There are huge, huge differences in countries and crime rates. You can look at differences in homicide rate, for example [1]. The united states has a pretty shockingly high homicide rate for a developed country (4.96 per 100k). This is 5x higher than France or Germany. On the other end you have Japan, which is about 5x lower than France or Germany (25x lower than United States).
But that aside, the important question is: is crime driving police activity, or are the police widely malicious and corrupt? I'll admit that I'm not knowledgable enough to give a good answer to this question, but I'm very skeptical of jumping to a conclusion based on selective evidence on social media or recent news coverage.
[1] https://en.wikipedia.org/wiki/List_of_countries_by_intention...