The confrontation came about because a gang of colonists were harassing a small group of British soldiers on guard duty. The Redcoats were hated in Boston as in many parts of the colonies because they represented the tyrannical grip that King George held on them. Some British soldiers had committed serious offenses, so the red uniform was looked upon with malice.
This night, March 5, 1770, a crowd gathered around the soldiers and began pelting them with snowballs and chunks of ice. Finally, someone yelled “Fire!” and muskets roared. Blood stained the snow.
The violence was contained with some quick action by the more clear-headed persons present, including Sam Adams. But the affair was far from over. The British soldiers must stand trial for murder.
This is where the story really gets interesting. Because it was John Adams, cousin to Sam who ended up as defense attorney for the British. Risking the ire of his fellow Americans, Adams stood up for the rule of law. He knew that in view of the many British depredations visited on the innocent colonists, his actions would not make him popular. But justice must come before reputation.
So it was that a devoted Son of Liberty, one of the loudest voices for independence from England, risked his good name to protect his enemies.
You can find this story and many more like it in Profiles of Valor.