I'm not sure what you're looking for here...
The kind of crimes we're talking about---assault, sexual harassment, rape---are committed every single day by men of pretty much all ethnic backgrounds. While we all know it happens, we tend to be unaware of particular crimes...but not these ones. Why is that?
It's because these crimes are politically useful. We're not supposed to be outraged because a woman was assaulted, we're supposed to be outraged because a migrant did it.