The Boston Tea Party was considered a criminal act, at least by the British authorities. Thankfully, the early Patriots were willing to stand up for what they believed in.
The Boston Tea Party was an "in your face" approach to let the British authorities know that the Patriots in the New World had their own ideas; their own agenda; and their own plans for self-government.
On December 16, 1773 -- not two years before the full scale American Revolution – Colonists; members of the secret Patriot organization termed the Sons of Liberty, and others in the New World disguised themselves as Mohawk Indians, then boarded ships loaded with East India Company tea, and dumped 342 chests of tea into Boston Harbor.
John Hancock and numerous others had been involved in the smuggling of tea into the Colonies, and promoting boycotts on tea from China, where the East India Company tea originated. Smuggling tea helped to make John and others quite wealthy.
Of course, the wealthy smugglers were not very happy with Parliament's favoring of the East India Company, since they knew that the company had engaged lobbyists to schmooze the members of Parliament. And, the Colonists were convinced that Parliament was selling them out to big business, and they took it as a direct attempt to restrict and control their new found freedoms in the New World; and they did not like that at all!
Prominent members of the Sons of Liberty included Paul Revere, Thomas Young, Joseph Warren, Alexander McDougall, Patrick Henry, John Hancock, Isaac Sears, John Lamb, James Otis, Thomas Crafts, Jr., John Adams, and his cousin, Samuel Adams, who was a leader of the New England resistance. Silas Downer, a so-called Forgotten Patriot, spoke as a Sons of Liberty member at one of the famed Liberty Trees in 1766.