4. c. 6) was an Act of the Parliament of the United Kingdom of Great Britain and Ireland which made it illegal to hold an outdoor meeting of more than 50 people without prior authorization.

[4][5] The law forbade all meetings of more than 50 people called "for the purpose...of deliberating upon any public grievance, or upon any matter or thing relating to any trade, manufacture, business, or profession, or upon any matter in church or state," unless the meeting had been summoned by an authorised official.

[6][7] Attendees were prohibited from carrying arms, and the display of flags, banners and other ensigns or emblems at the assembly was banned.

[9] The act also established regulations for places where lectures or debates were held, requiring these to be licensed and allowing officials to inspect them.

This was one piece of legislation among many others that blackened the reputation of Lord Liverpool's government until the Prime Minister's cabinet reshuffle in 1822, which ushered in Enlightened Liberal Toryism, an ideology that characterised British Politics during the mid-1820s.