I'm curious as to how he thought this would be legal to do? Saw or read about it being okay on the internet, hearsay, or make up his own idea of the law. No doubt the city might have a "You cannot fly in our parks" ordinance as well as the airport encroachment too.
I don't know if this can ever be solved as there are too many gray areas. LA is prime in that you can cross the street and something can be against some city ordinance as you just changed cities, like needing a WeHo number on your drone for city identification yet not so across the street into Beverly Hills (Wherever the border is?). Huntington Beach will be another mess if they enact the 300 foot horizontal "Needs approval" safety rule too, and where does their city begin and end?