In 1799, English Freemasonry almost came to a halt due to Parliamentary proclamation. In the wake of the French Revolution, the Unlawful Societies Act 1799 banned any meetings of groups that required their members to take an oath or obligation. The Grand Masters of both the Moderns and the Antients Grand Lodges called on Prime Minister William Pitt (who was not a Freemason) and explained to him that Freemasonry was a supporter of the law and lawfully constituted authority and was much involved in charitable work. As a result, Freemasonry was specifically exempted from the terms of the Act, provided that each private lodge's Secretary placed with the local "Clerk of the Peace" a list of the members of his lodge once a year. This continued until 1967 when the obligation of the provision was rescinded by Parliament.
Is there an answer to this question (If it cannot be answered, say "unanswerable"): Who gave the Freemasons an exemption of the Act of 1799?
Prime Minister William Pitt