IIRC, there was a bump in the US crime rate after Katrina. It was usually attributed to New Orleans cooking the crime books, those criminals getting displaced, and the LEOs in their new location reporting their criminality.
So, yes, many LEO shops cook the books.
Oh, I forgot to mention the riots that occur outside Chicago public schools when they let out in particular neighborhoods. They are not reported as riots, the same way most riots were not reported as riots in big cities during the 1970s and 1980s.