Harry is not allowed to court and marry Marion Murphy just because he wants some decent food. On the other hand, if she comes on to him, anything goes.
Harry is not allowed to to whisper "Aloha, you half-monster bastard" in Kincaid's ear when when Kincaid is on the edge of death. It makes Ivy unhappy.
Harry is not allowed to hum "Afternoon Delights" during his monthly diplomatic meeting with Lara Raith. While it is a cute tune, it sets the wrong tone and could get him killed.
Harry is not allowed to hum "England swings" endlessly in an attempt to try and goad the Merlin into trying to break the First Law.
Harry is not allowed to use magic to help Butters win the polka contest again this year. The Council passed a whole new Law of Magic about that...
Harry is not allowed to slip Karrin a dose of Three-eye just before her date with Kincaid...
The next time Kincaid and Murphy go to Hawaii, Harry is not allowed to mail a manila envelope full of incriminating evidence about Kincaid to McGarrett. That's Ebenezar's job...deniability is everything.