The Hughes Court struck down a California law that prohibited the display of red flags as opposition to the U.S. government in Stromberg v. California (1931). Yetta Stromberg, a 19-year-old member of the Young Communist League, was arrested and convicted of violating the red-flag law for displaying such a flag at a summer camp where she taught history. The California “Red Flag” Law stated: “Any person who displays a red flag, banner or badge or any flag, badge, banner, or device of any color or form whatever in any public place or in any meeting place or public assembly, or from or on any house, building or window as a sign, symbol or emblem of opposition to organized government or as an invitation or stumulus to anarchistic action or as an aid to propaganda that is of a seditious character is guilty of a felony.”

The Hughes Court reversed her conviction by a 7–2 vote, reasoning that the statute would sweep within its prohibition “peaceful and orderly opposition to government by legal means and within constitutional limitations.” Such a broad prohibition, the Court wrote, was “repugnant to the guaranty of liberty contained in the Fourteenth Amendment.”

The case is important because it establishes the principle that the First Amendment protects more than just verbal or written expression. It also involves certain forms of expressive conduct, such as the display of the red flag or the wearing of certain clothes.