They claim Adams defended a British soldier who killed Americans at the Boston Massacre. One problem, the Boston Massacre took place in 1770 and the trial was in the King's Court, with Adams an attorney admitted to the King's bar - 6 years before the Declaration of Independence. So at the time Adams was representing a fellow countryman who himself was serving their common country.
With or without the Revolution America was going to far outdo the old homeland ~ if it hadn't have happened we'd probably have reverted the UK back to sheep farms and oak lots for the pigs ~ like it oughta' be.