This article reexamines the parliamentary impeachment of the Duke of Buckingham, the royal favorite of King Charles I, by placing this event in the broader contexts of political culture and social change in early Stuart England. Buckingham's enemies based the impeachment on “common fame,” claiming that his faults were a matter of public knowledge. Charles, however, believed that the charges were based on seditious rumors. The impeachment undercut an important element of elite rhetoric that associated rumor with the rebellious multitude, revealing ideological divisions over the nature of grievances and the legitimacy of popular speech. The article contextualizes the impeachment within 1620s underground literature that purported to present the views of the common people, arguing that there was a wider tendency to ventriloquize public opinion. When Buckingham's allies produced their own tracts featuring the persona of the “honest ploughman,” appeals to the authority of public opinion were clearly gaining in strength. By explaining this development in political culture with reference to the growth of a more politically reliable “middling sort,” the article contributes to debates about the relationship between social change and political conflict in early Stuart England.