Are Drawings On Fence Religious Symbols or Graffiti?

A pagan couple in Des Moines, Iowa are appealing an order by the neighborhood inspections division that is demanding they remove graffiti from their fence. Homeowner Ryle MacPebbles however says the drawings are pagan religious symbols he placed on the fence to protect their home and ward off evil energy. He says the city is attacking his religion. Yesterday's Des Moines Register says that the city code defines as graffiti any "inscription, drawing, picture, letter, number, symbol or other written communication" on a surface not intended for such use.