Is Cleaning a Crime?

Alexandre Orion is cleaning São Paulo’s tunnels by scraping the deposited vehicle exhaust soot from the walls to make hundreds of skulls. Even though the police turned up several times, they couldn't do much as cleaning is no crime. After some time the São Paulo municipal authority started their own cleaning mission, consequently only cleaning the parts already cleaned by Alexandre. Again the skulls appeared on the remaining soot "canvas", and this time the city decided to clean all of the tunnels.

via placeboKatz and Birdhouse.