A few thousand or even a few hundred years ago: sure. https://www.youtube.com/watch?v=sQjT3z0ti6U

But not 20 or 50 years ago.

One reason why murder is a widely cited stat for police effectiveness is that it is harder to falsify the top line number. But as others have pointed out it's not impervious to being gamed.

That wouldn’t affect the clearance rate