Final answer:
Graffiti on subway cars is illegal because it may lead to property damage, could provoke other criminal activities, and raises issues regarding public safety and urban cleanliness. Despite its potential as an artistic and political medium, the legal system prioritizes the maintenance of order and safety in public spaces.
Step-by-step explanation:
Graffiti writing on subway cars is illegal, and this is a contention with both cultural and legal implications. On one hand, graffiti has been a form of cultural expression and political activism since the 1960s.
It can serve as a powerful statement, especially during political uprisings where it reflects societal views and challenges the status quo. The case of renowned street artist Banksy exemplifies how graffiti can blur the lines between vandalism and valued art, raising awareness of social and political issues.
However, graffiti is also associated with visual pollution and can signify territorial boundaries between competing gangs, leading to safety concerns as emphasized in territories such as East Los Angeles.
The illegal nature of graffiti writing is supported by theories that suggest maintaining visual order in communities is critical. Promptly addressing visual disarray, like graffiti, can be essential in preventing the escalation of urban decay and crime, as proposed in the broken windows theory.
Therefore, while graffiti can be a form of art and activism, writing on subway cars is illegal because it often leads to property damage, may encourage further criminal activity, and can cause concern over public safety and maintenance of urban environments.