I would argue that the Declaration of Independence protects us more against tyranny than the Constitution. Reason: the DoI lays out justifications for taking up arms against your government.
The Constitution may be altered ... or "interpreted" ... or ignored ... at the whims of politicians and citizens. And has been at various points in history.
But the Declaration of Independence has inspired people around the world to list their grievances against governments ... and, if necessary, to take up arms in rebellion against injustice.