The Boston Massacre refers to the violence which erupted when a group of citizens assembled outside the statehouse to protest against the British soldiers' presence in the town. In this course of this event, five colonists were killed. While the patriots held red coats, soldiers for the brutal murder, Captain Thomas Preston along with his eight British soldiers called it an act of self-defense. John Adams who himself was a patriot agreed to take the case of the British soldiers.
Explanation: The subject or who is performing the action is not clear and in an active sentence, there is importance placed on the person who is performing the action.
The sentence that uses the word them as an indirect object would be Leo sent them a postcard from NASA. Hope this helps and good luck with whatever it is you're doing!