[5][6]Legal walls are different from commissioned murals or commercial graffiti as writers and artists are given relative freedom in what they create,[1] although hateful messages are often disallowed.
[2] Privately owned walls may need council permission to exist in some jurisdictions, where graffiti-style art is illegal in public even if done on personal property.
[9] In typical graffiti spaces, going over someone elses writing (or "capping") is an insult, but legal walls are often repainted multiple times a day with no disrespect taken by artists.
[10] Some writers believe that legal walls defeats the purpose of graffiti, as a rebellious act[3] to reclaim public space.
[11] Other research has shown that legal walls reduce illegal graffiti by giving writers a safer, often visible space for their art.