I am not sure how you define "amazingly competent, well-trained, and effective", but in at least one respect the Japanese police is highly negligent: https://www.businessinsider.com/afp-getting-away-with-murder...

Additionally, this statement does not depict what many (most?) people would consider an effective or competent police force: "she was not [Japanese], which meant that the police were... less incentivized to help her".

I am currently a foreigner living in a Scandinavian country, and I simply cannot imagine facing the same kind of discrimination from the police force (nor from other authorities) here. I think many (most?) people would agree that an effective/competent police force is not one which ends up driving foreigners out of the country by virtue of being unwilling to afford foreigners equality before the law.