Why did John Adams believe the Boston Massacre soldiers were innocent?

“The Part I took in Defence of Cptn. Preston and the Soldiers, procured me Anxiety, and Obloquy enough. It was, however, one of the most gallant, generous, manly and disinterested Actions of my whole Life, and one of the best Pieces of Service I ever rendered my Country. Judgment of Death against those Soldiers would have been as foul a Stain upon this Country as the Executions of the Quakers or Witches, anciently. As the Evidence was, the Verdict of the Jury was exactly right.”   –John Adams

John Adams decided to defend the soldiers and commander of the troops in the Boston Massacre.  He did so at a time when tensions were high in Massachusetts and political fallout was very possible.  As a lawyer, it is not your job to judge guilt or innocence about your clients.  The duty of the attorney is to ensure that clients are given a solid defense.  What can be said about Adam's defense of the British soldiers is that it was very effective.  In the case of the commander, Thomas Gage, Adams and his legal team were able to prove reasonable doubt about whether he was the man that yelled "fire" to his troops.  Adams believed that members of the mob may have yelled the command which resulted in the deaths of American colonists.  In the case of the soldiers, Adams painted a scene of chaos and violence in which the troops had to fight for their lives.  Adams believed that it was the right of the British soldiers to defend themselves from imminent bodily harm or even death.  

Why did John Adams defend the British soldiers after the Boston Massacre?

Although he was a staunch opponent to the perceived tyranny of the English Crown in the colonies, John Adams strongly believed in the rule of law. As much as he might have wanted to see the killers of those who died at the Boston Massacre punished, he also felt that everyone should be entitled to a fair trial. Part of Adams' motivation was to show the world that Bostonians were not some uncivilized backwater colonists. Rather, by insisting that the indicted soldiers get a fair defense, Adams was making the point that Bostonians were law-abiding British citizens.

Furthermore, Adams recognized that this case was not as straightforward as it seemed. There were discrepancies in witnesses' accounts that led Adams to believe that the soldiers might actually have a case. It was on the basis of inconsistent testimony and conflicting accounts of what happened on March 5, 1770, that Adams was able to secure the final verdicts in the two cases he took. In one of his closing statements, Adams summed up his likely feelings about this case by saying

Facts are stubbrn things; and whatever may be our wishes, our inclinations, or the dictates of our passion, they cannot alter the state of facts and evidence."

What was John Adams aiming to prove by defending the British soldiers in the Boston Massacre?

As American politics would later show, John Adams was a conservative. Despite the radical nature of American independence, Adams was not himself a radical, despite being a chief advocate for independence. Where someone like Thomas Jefferson would support the idea of a revolution every twenty years and watering the tree of liberty with the blood of tyrants, Adams was definitely a proponent of law and order. In conservative, aristocratic British eyes, all Americans who didn’t side with the king were radicals out to destroy society. Granted, there were a lot of radicals in Boston in the period leading up to the Boston Massacre, and men like Adams were fully willing to recognize them as such. Adams feared these radicals as much as the British did.

It is questionable whether or not the Americans involved in the Boston Massacre should be called patriots. They were not involved in a peaceful protest. They threw rocks and snowballs at the British troops, so the troops were certainly provoked into firing their weapons. The Boston Massacre was not a battle; it was a riot. This riot inflamed American radicals such as Paul Revere, who used the incident as a public relations tool to whip up even more hysteria against the British. The event, no doubt, made the king and his allies feel justified in their view of Americans as radicals. But by defending the British soldiers involved in the Boston Massacre, Adams showed both his American countrymen and the British establishment that America was not controlled by radicals. The American Revolution was going to be a revolution in favor of law and order. America was not and would not be subjected to mob rule.

John Adams had the utmost respect for the law, believing that even the British soldiers responsible for the deaths of five people deserved council and fair trials. Adams wanted the fledgling nation founded on the ideals of justice and equality. Regardless of their actions and their influence in the political environment of the American colonies, Adams was adamant that the soldiers be treated fairly. Adams's actions were brave in that he opened himself up to the scrutiny and resentment of the radical members of the revolution.

Adams also emphasized that revenge begot only more conflict. The colonies had long experienced exploitation at the hands of the British government. If the leaders of the American Revolution permitted the taking of revenge against the British, America would be thrown into an endless war founded on bitterness and spite.