The broken windows theory is a criminology theory of the norm-setting and signaling effect of urban disorder and vandalism leads to additional crime and anti-social behavior. The theory states that maintaining and monitoring urban environments in a well-ordered condition may stop further vandalism and escalation into more serious crime. Consider this example: An abandoned building with a few broken windows. Alone it poses no threat. However a few vandals come along and spot these broken windows and decide to break more of them. The building, because of its condition later gets vandalized with spray paint. Since it looks completely run down, a few homeless people break in. With time, they light fires, destroy the inner workings of the building and become squatters. This domino effect is the premise behind the broken windows theory. The theory is that minor crimes, if left unnoticed, will eventually escalate into bigger, more serious crimes. This is the same theory that the NYPD policy uses. The New York Police department's program intends on stopping people in high crimes areas to search for weapons and other substances. The program’s purpose is to remove guns off the street before they are used in more serious crimes. In the context of this allegory, the NYPD aims to fix the broken windows before the squatters get in.