Kansas City, Death and Taxes

At a recent gathering of religious leaders, one earnings-tax supporter told those gathered that if the earnings tax is defeated on April 5, "We're going to lose 800 cops over 10 years." Of course there is no way that any city leadership would allow that to happen, but this is the sort of scare tactic the city is relying on to get "yes" votes.
The speaker also talked about the history of the tax, claiming that it was promulgated to increase public safety spending in response to the high murder rates in the late 1960s. We looked up the murder statistics for Kansas City, and indeed there was an increase in the late 1960s, peaking at 134 homicides in 1970. The number decreased afterward, but never returned to its previous rate. The speaker offered no evidence to support the idea that the imposition of a regressive flat tax had anything to do with declining murder rates. He certainly offered nothing to suggest that phasing out the earnings tax now would lead to an increase in homicides. The tactic seems intent not on educating voters, but on frightening them.
Are things better now? Over the last few years, Kansas City has averaged 101 murders each year, and the trend is pretty flat since 2000. Overall, Kansas City has one of the highest murder rates in the United States, and while national data for 2015 are not yet available, the jump in homicides in 2014 may return us to the top ten, where we were in 2013.
Back in the 1960s, Kansas City had a high murder rate. Today we have a high murder rate and an earnings tax. Is this the type of "progress" of which Kansas Citians can be proud?