He has a good case. Regardless of whether or not the bull was legally placed, the fact that the city allowed it to stay for so long is an "implied contract." The little girl, on the other hand, hasn't been there long enough to imply a contract. It's a basic real estate law concept. Now, imagine if you painted the Mona Lisa and had it prominently displayed as the centerpiece of an art collection...then some kid spray paints some awesome, Kakaako-quality graffiti art across the room from it. That would certainly devalue the artistic presence of your Mona Lisa, right? Tort law exists to "make things right" and, therefore, could conceivably rule in his favor.