A main task of the Transit Police was its defense of the subway system from defacement. Graffiti was very prominent throughout the subway system by the mid-1980s and the city government took a hard line in response, though some saw it instead as a "social trend" and a sign of diversity. The Transit Police, and specifically a new unit called the Vandal Squad began to fine and arrest those painting graffiti. They also made a policy to remove any work of graffiti within 24 hours of its creation. By the end of the 1980s, the Transit Police had effectively solved the problem of graffiti in the New York City subway system.