If you look at the numbers, more officers ACTUALLY correlate to substantial RISES in crime...
There are approximately 3 times more sworn officers per thousand citizens today than the US had in 1950.
Crime in the US was relatively stable (per 1000) from WWII- the late 1960s, but then began an ever-increasing climb hrough the 1970's, and peaked in the mid 2000's. Violent crime has actually been DECLINING in most regions for the last 2 or 3 years (with a few notable exceptions--mostly in "sanctuary" cities and southern border counties)
During that same period, there was a steady increase in the number of sworn officers, but there was a spike in LE hiring in the mid-90's and again in the early 2000's.
Of course, the delightful thing about statistics is that correlation DOES NOT equal causation...
During that same period, from 1970-2009, the importation of automobiles from Japan grew exponentially, so by the same logic, one could argue that more Toyotas cause more crime. (and judging from what I've seen on the DC beltway, there may be some truth to that...)
During that same period, circumcisions of American male infants has dropped off significantly. So perhaps intact foreskins actually cause more crime.
During that same period, mortgage-holders increased as more and more people bought their own houses. So perhaps increased interaction with Loan Officers causes crime. (well, this is pretty much a given, but you get the point...)
During that time, the shift in terms of the majority percentage of GDP from consumer good to the production of military hardware nearly flip-flopped. So perhaps it is working in factories that build military equipment that causes crime.
During that time, the nation-wide demand for bacon has dropped dramatically, and the demand for "organic" food has skyrocketed. So perhaps "healthy" eating causes more crime. (it's all the fault of those hippies!)
What it all comes down to is that the NUMBER of cops on the street has little if any real affect on the number of crimes committed, because these two events are NOT directly related in any meaningful way.
What causes increases in crime is poverty, the disintegration of the family structure, lack of upright morals with regards to child rearing, and the disconnection (in families, schools, and entertainment) between actions and consequences.
When children are allowed to run amok as children, grow up in a culture that agrandizes drugs, crime, and entitlement, and are PUNISHED for excellence and honesty and rewarded for mediocrity and laziness, increased crime is pretty much a "gimme".
