All, right!
After reading on this, I just could not keep my mouth shut. This one acually caused me to cringe.
First:
The morality of the character is not defined by the game master. It is defined by the character. Period. Why? Because the game master CANNOT know the mind of the player. That simple.
The only thing the game master can base his views on is ALIGNMENT. Alignment equals the ACTIONS taken by the character. Actions define alignment.
Let us look at alignment then:
Lawful: there are many ways to interpert this. What are his priorities? Here are some basic law groups: Personal ethics, church law, god's law (these CAN differ), local legal law, law of common sense (which is not the paladin's friend). The question is which law is most and least important to him.
Good: Wow, this is wide open. How about "Do least harm, and most help." Simple, yet satisfying...
Now combine the above good with the above law: You could easily come up with a paladin that refuses to risk evil, killer, cutist children from getting loose once he has them. He had no proof that the others could contain them. Heck he had no proof he could succeed in killing them... What he did is take the safest path for the most lives. Sorry, no real dice on alignment violation either.
So what we have here, is the game master saying that his GOD was not happy with what he did, period. No violation but ticking off the being that gave him his abilities.
God giveth, god taketh away.
As for you, gamemaster: I think you were just being nasty because the player was messing with your carfully wrought plot. Happens to us all, but watch yourself for it.
Why? Because the only alignment violation you MIGHT be able to pin on him is being neutral good in the moment.
You just showed the player that his god is fickle. His smite works on the little buggers, but he was not supposed to use it on THEM... What next? He can't heal someone because they MIGHT kill somebody later?
Be consistant. They can't know what you are thinking either.
Mr Oberon.
"Player of 8 paladins, GM of who knows..."