How does that Daily Mirror cover provide us with any information as to German police impinging upon the rights of others and subsequently covering it up?
Because "They" are all the same; whether the "They" in question is Muslims, Refugees, or Police Forces.
The idea that "They" are all the same (and all as bad as whatever the worst example is that can be found); and the "We" are likewise monolithic (and all are as noble as the noblest example that can be found) is, I believe, the 'Socialist' part of 'National Socialism'.
Hence the lack of any discussion of the crime rates of non-immigrant Germans; to the National Socialist mind, such information is of no value - all we need to look at are the bad things done by Them, and the good things done by Us. We can simply assume that good things done by Them and bad things done by Us are outliers, and can, should and must be ignored.