This act was passed to assert the authority of the British government to tax its subjects in North America after it repealed the much-hated Stamp Act. The purpose of the Declaratory Act of 1766 was to affirm that Great Britain had complete authority to tax its American colonies.In general the act is descryibed simply as a theoretical gesture or political tactic to ease the passage of the Stamp Act. An Act for the better securing the Dependency of His Majesty's Dominions in America upon the Crown and Parliament of Great Britain. The taxation measure is designed to raise revenue for British military operations in America. Declaratory Act (1766). The Declaratory Act. The repeal of the Stamp Act did not mean that Great Britain was surrendering any control over its colonies. The colonies had resisted the implementation of direct taxes, but the Declaratory Act reserved Parliament's right to impose them. 25 Stamp Act Congress meets in Philadelphia to discuss the crisis. 1766.