Encyclopedias, Almanacs, Transcripts, and Maps
- Mapp v. Ohio 367 U.S. 643 (1961)
- Mapping Technology
- Marbury v. Madison 1 Cranch 137 (1803)
- Marchetti v. United States 390 U.S. 39 (1968) Grosso v. United States 390 U.S. 62 (1968) Haynes v. United States 390 U.S. 85 (1968) United States v. United States Coin & Currency 401 U.S. 715 (1971)
- Marketplace of Ideas
- Marriage and the Constitution
- Marsh v. Alabama 326 U.S. 501 (1946)
- Marsh v. Chambers 463 U.S. 783 (1983)
- Marshall Court (1801–1835)
- Marshall v. Barlow's, Inc. 436 U.S. 307 (1978)
- Marshall, John (1755–1835)
- Marshall, Thurgood (1908–)
- Marshall, Thurgood (1908–1993) (Update)
- Martin v. Hunter's Lessee 1 Wheaton 304 (1816)
- Martin v. Mott 12 Wheaton 19 (1827)
- Martin, Luther (1748–1826)
- Maryland Toleration Act (April 2, 1649)
- Maryland v. Craig 497 U.S. 836 (1990)
- Mason, George (1725–1792)
- Massachusetts Bay, Colonial Charters of (1629, 1691)