1. The Virginia and Kentucky Resolutions (1798)
In response to the Alien and Sedition Acts passed by Congress, Virginia and Kentucky passed resolutions declaring those federal laws unconstitutional. Drafted secretly by Thomas Jefferson and James Madison, these resolutions asserted the principle of ‘nullification,’ claiming states had the right to invalidate federal laws deemed unconstitutional in their view. This foundational episode set an early precedent for state resistance to federal authority.
