List of United States Supreme Court cases, volume 242

The Supreme Court is established by Article III, Section 1 of the Constitution of the United States, which says: "The judicial Power of the United States, shall be vested in one supreme Court . . .". The size of the Court is not specified; the Constitution leaves it to Congress to set the number of justices. Under the Judiciary Act of 1789 Congress originally fixed the number of justices at six (one chief justice and five associate justices).^[1] Since 1789 Congress has varied the size of the Court from six to seven, nine, ten, and back to nine justices (always including one chief justice).

When the cases in volume 242 were decided the Court comprised the following nine members:

Portrait	Justice	Office	Home State	Succeeded	Date confirmed by the Senate (Vote)	Tenure on Supreme Court
	Edward Douglass White	Chief Justice	Louisiana	Melville Fuller	December 12, 1910 (Acclamation)	December 19, 1910 – May 19, 1921 (Died)
	Joseph McKenna	Associate Justice	California	Stephen Johnson Field	January 21, 1898 (Acclamation)	January 26, 1898 – January 5, 1925 (Retired)
	Oliver Wendell Holmes Jr.	Associate Justice	Massachusetts	Horace Gray	December 4, 1902 (Acclamation)	December 8, 1902 – January 12, 1932 (Retired)
	William R. Day	Associate Justice	Ohio	George Shiras Jr.	February 23, 1903 (Acclamation)	March 2, 1903 – November 13, 1922 (Retired)
	Willis Van Devanter	Associate Justice	Wyoming	Edward Douglass White (as Associate Justice)	December 15, 1910 (Acclamation)	January 3, 1911 – June 2, 1937 (Retired)
	Mahlon Pitney	Associate Justice	New Jersey	John Marshall Harlan	March 13, 1912 (50–26)	March 18, 1912 – December 31, 1922 (Resigned)
	James Clark McReynolds	Associate Justice	Tennessee	Horace Harmon Lurton	August 29, 1914 (44–6)	October 12, 1914 – January 31, 1941 (Retired)
	Louis Brandeis	Associate Justice	Massachusetts	Joseph Rucker Lamar	June 1, 1916 (47–22)	June 5, 1916 – February 13, 1939 (Retired)
	John Hessin Clarke	Associate Justice	Ohio	Charles Evans Hughes	July 24, 1916 (Acclamation)	October 9, 1916 – September 18, 1922 (Retired)

In Caminetti v. United States, 242 U.S. 470 (1917), the Supreme Court interpreted the scope of the Mann Act. The Court decided the Mann Act applied not only to purposes of prostitution but also to other noncommercial consensual sexual liaisons, and that consensual extramarital sex falls within the definition of "immoral sex." The case was one of the first in which the Court embraced the “plain meaning rule”. This is a form of legislative interpretation that focuses strongly on the literal text of a statute. In its most extreme form, the plain meaning rule does not point outside the words of the statute at any other sources to find legislative intent, if the Court decides that the rule is "plain" from its text alone.

Under the Judiciary Act of 1789 the federal court structure at the time comprised District Courts, which had general trial jurisdiction; Circuit Courts, which had mixed trial and appellate (from the US District Courts) jurisdiction; and the United States Supreme Court, which had appellate jurisdiction over the federal District and Circuit courts—and for certain issues over state courts. The Supreme Court also had limited original jurisdiction (i.e., in which cases could be filed directly with the Supreme Court without first having been heard by a lower federal or state court). There were one or more federal District Courts and/or Circuit Courts in each state, territory, or other geographical region.

The Judiciary Act of 1891 created the United States Courts of Appeals and reassigned the jurisdiction of most routine appeals from the district and circuit courts to these appellate courts. The Act created nine new courts that were originally known as the "United States Circuit Courts of Appeals." The new courts had jurisdiction over most appeals of lower court decisions. The Supreme Court could review either legal issues that a court of appeals certified or decisions of court of appeals by writ of certiorari. On January 1, 1912, the effective date of the Judicial Code of 1911, the old Circuit Courts were abolished, with their remaining trial court jurisdiction transferred to the U.S. District Courts.

Bluebook citation style is used for case names, citations, and jurisdictions.

• "# Cir." = United States Court of Appeals
  • e.g., "3d Cir." = United States Court of Appeals for the Third Circuit
• "D." = United States District Court for the District of . . .
  • e.g.,"D. Mass." = United States District Court for the District of Massachusetts
• "E." = Eastern; "M." = Middle; "N." = Northern; "S." = Southern; "W." = Western
  • e.g.,"M.D. Ala." = United States District Court for the Middle District of Alabama
• "Ct. Cl." = United States Court of Claims
• The abbreviation of a state's name alone indicates the highest appellate court in that state's judiciary at the time.
  • e.g.,"Pa." = Supreme Court of Pennsylvania
  • e.g.,"Me." = Supreme Judicial Court of Maine

• [1] Case reports in volume 242 from Library of Congress
• [2] Case reports in volume 242 from Court Listener
• [3] Case reports in volume 242 from the Caselaw Access Project of Harvard Law School
• [4] Case reports in volume 242 from Google Scholar
• [5] Case reports in volume 242 from Justia
• [6] Case reports in volume 242 from Open Jurist
• Website of the United States Supreme Court
• United States Courts website about the Supreme Court
• National Archives, Records of the Supreme Court of the United States
• American Bar Association, How Does the Supreme Court Work?
• The Supreme Court Historical Society