At least they are disguising it. Australia has, in the state of SA the "Police Complaints and Discipline Act 2016", that expressly allows police officers to investigate their own corruption, and when they inevitably conclude they did nothing illegal, anyone who complains to anyone other including human right's organisations will be arrested and charged.

Source: I was arrested by my ex-wife's boyfriend, who denied all my human rights in detention. All his ridiculous charges were thrown out, but he, and his police partner was allowed to investigate himself as to whether he violated any laws. I then received a threatening letter from the Attorney-General telling me I would be charged if I brought it up the particulars of it with anyone.