This article points to PD but also other private groups getting involved to lower crime in NY -
http://www.city-journal.org/html/how-new-york-became-safe-full-story-13197.html"the Grand Central Partnership (also led by Biederman) began reducing disorder in the 75 blocks surrounding Grand Central by employing private security and hiring the homeless to clean the streets. Thirty-two more Business Improvement Districts (BIDs) were developing similar approaches in New York."
"Neighborhood organizations, too, began demanding that order be restored"
Similar to what KC has done with the Downtown CID and Main Street CID. Neighborhood organizations seem to help too
This article points to lowering unemployment, raising minimum wage, and improved economy along with the growth in the police force in NY.
http://www.nber.org/digest/jan03/w9061.html"This study shows that a single percentage point decline in the jobless rate decreases burglary by 2.2 percent and motor vehicle theft by 1.8 percent. Increases in the real minimum wage also significantly reduce robberies and murders: 3.4 to 3.7 percent fewer robberies with a 10 percent increase in the minimum wage and 6.3 to 6.9 percent fewer murders."
This article questions how much Rudy's policies had in reducing crime
http://www.politifact.com/truth-o-meter/article/2007/sep/01/how-much-credit-giuliani-due-fighting-crime/"Independent studies generally have failed to link the tactics of the Giuliani administration with the large decrease in crime rates."
"many criminologists believe the decline in New York, as in Chicago, San Diego, Miami and elsewhere, was the result of a complex mix of social and demographic changes, including a break in the crack cocaine epidemic, an improving economy, and increased prison terms for proven lawbreakers.
Better policing tactics and policies were likely part of it, experts say, but not to the extent Giuliani claims."
This article also puts into question all the other factors that contributed -
https://www.washingtonpost.com/news/fact-checker/wp/2016/08/19/trumps-claim-attributing-the-20-year-new-york-city-crime-decline-to-giulianis-policies/Finally this presentation from KCPD does show violent crime has been dropping in KCMO since 1990
http://kcmo.gov/police/wp-content/uploads/sites/2/2016/02/HistoricalViolentCrimePresentationFinal.pdf
