I think that the British soldiers acted in self defense during the Boston Massacre. The colonists were threatening and provoking the soldiers by shouting vulgarly, beating people with clubs, and throwing rocks covered in snow, so I believe that the soldiers had a right to fight for their lives.
Just take a moment to imagine the Boston massacre, it’s late at night and people are tired and confused. The colonists are shouting “Fire and be damned, who cares! Damn you, you dare not fire,” (Exhibit B) and the British soldiers are ready to defend but don’t know what’s going on. Captain Preston says to hold fire but the the colonists are screaming the opposite, it’s dark outside so it’s hard to see who is who, a british soldier accidentally fires