In his closing statement, John Adams actually blamed Crispus Attucks, "whose very looks was enough to terrify any person" for instigating the shooting. According to Adams, Attucks charged the soldiers and "with one hand took hold of a bayonet, and with the other knocked the man down: This was the behavior of Attucks; to whose mad behavior, in all probability, the dreadful carnage of that night, is chiefly to be ascribed."
However, in the 19th Century, Boston abolitionists began to specifically exaggerate the importance of Crispus Attucks, an exaggeration that continues to this day. After the Civil War, a memorial was built on the Boston Common to the "victims of the Boston Massacre", with Crispus Attucks prominently mentioned.
So perhaps the real legacy of Crispus Attucks is that he may be the first minority whose status was deliberately elevated for political purposes. Today, there are public schools as far away as Texas named after Crispus Attucks. In 1998, the US Mint coined a "Crispus Attucks Silver Dollar."
Incidentally, people forget that the exoneration of the British soldiers was due in no small part to the testimony of a courageous black slave known only as "Andrew." But virtually no one remembers Andrew, and there are no schools or statues named after him.
Today, March 5, is actually the 241st anniversary of the Boston Massacre. There is a credible reenactment of the event every year around 9pm. Definitely worth attending (See video).