Cologne and few prosecutions?

So the police and prosecutors for whatever reason just close the case.

Die Staatsanwaltschaft Oldenburg stellte die Ermittlungen ein, schrieb dem Opfer: „Es ist durchaus denkbar, dass der junge Mann Ihnen auf diese Weise sein Interesse an Ihnen mitteilen wollte.”
The Oldenburg prosecutor discontinued the investigation, wrote the victim: “It is quite possible that the young man wanted to be notified in this way be interested in you.” 
http://www.bild.de/regional/bremen/sexueller-missbrauch/staatsanwalt-verhoehnt-grabsch-opfer-49300650.bild.html

One may have to use google translate.
And another reason why these crimes are not investigated, by the head of police.

Holger Munch, president of Germany’s Federal Police, said: “There is a connection between the emergence of this phenomenon and the rapid migration in 2015.”

He added many of those responsible for the sex attacks would probably escape justice because of limited CCTV footage and the fact many were masked.

He said: “We have to presume that many of these crimes will never be fully investigated.”
http://www.express.co.uk/news/world/688767/German-police-revise-up-number-of-victims-of-Cologne-migrant-sex-attacks

The prosecutor Ulrich Bremer says you are wrong

Cologne’s public prosecutor Ulrich Bremer said only three of the suspects had recently arrived in Germany. The rest were of Algerian, Tunisian or Moroccan origin, while three were German citizens. According to the report, he also said that of 1,054 complaints received 600 were connected to theft rather than a sexual offence.

However, Bremen denied the reports the following day as “total nonsense,” telling Associated Press that “the overwhelming majority of persons fall into the general category of refugees.” According to AP, Bremer said 73 suspects have been identified so far that include 30 Moroccan nationals, 27 Algerians, four Iraqis, three Germans, three Syrians, three Tunisians, and one each from Libya, Iran, and Montenegro. A total of 1,075 criminal complaints have been filed, including 467 alleging crimes of a sexual nature ranging from harassment to rape. Twelve of the 73 suspects are linked to sexual crimes, though only one of those—a Moroccan asylum-seeker who entered Germany in November—is in custody, he said.
https://broadly.vice.com/en_us/article/rape-was-a-problem-in-germany-long-before-the-refugees-arrived

Doubtlessly there is an example of a “native” German raping, but the sheer numbers are totally opposite in fact on the Cologne situation, besides the politicized police, and keeping things quiet.