First of all, it's NY State, not NYC, and Article 35.10 of the Penal Code says you are allowed to use physical force for self-defense or in the defense of others, but the very next clause is 35.15 which says that you have a duty to retreat unless there is immediate danger.

In a NY court of law you could argue that you were acting in the defense of others, but you would not be able to prove that there was imminent danger.