Answer: British officers shot at the crowd because the citizens were being verbally abusive and assaulted the officers.
Explanation:
The citizens were angry with appointed officials that were enforcing legislation that the people were against. There was only one British sentry that was stationed there and he was being verbally abused by an angry mob of people. More soldiers came to help him, it was believed to be a total of 8, and they were also being verbally harassed.
As the mob, a large crowd of people grew the more angrier they became. They started assaulting the officers with sticks, clubs, rocks, and even snowballs.
The officers began shooting into the large crowd of people and killed 5 people, 3 of whom died at the scene. The officers did not have orders to began shooting and did this on their own.
This event is known as the Boston Massacre.