Yep, really.
In nearly all cities across the US, Chiefs of Police serve at the pleasure of the Mayor (and sometimes city council).
Leftist DemoRat politicians have discovered that they can promise a reduction in crime and when elected, they order the Chief to "reduce the crime statistics" or be fired and replaced with "someone who will". The message is clear, and the Chief controls the advancement and retention of all those officers under him. If crime stats don't go down, a lot more cops than the Chief will be losing their jobs or advancement.
I know this to be a fact from personal experience in San Francisco, another leftist city with a "falling" crime rate.
But yes, you are right. Remember the book, "How To Lie With Statistics"? Widely used and applied by many of 'em.