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The federal government is obliged by many constitutional provisions to respect the individual citizen’s basic rights. Some civil liberties were specified in the original document, notably in the provisions guaranteeing the writ of habeas corpus and trial by jury in criminal cases (Article III, Section 2) and forbidding bills of attainder and ex post facto laws (Article I, Section 9). But the most significant limitations to government’s power over the individual were added in 1791 in the Bill of Rights. The Constitution’s First Amendment guarantees the rights of conscience, such as freedom of religion, speech, and the press, and the right of peaceful assembly and petition. Other guarantees in the Bill of Rights require fair procedures for persons accused of a crime—such as protection against unreasonable search and seizure, compulsory self-incrimination, double jeopardy, and excessive bail—and guarantees of a speedy and public trial by a local, impartial jury before an impartial judge and representation by counsel. Rights of private property are also guaranteed. Although the Bill of Rights is a broad expression of individual civil liberties, the ambiguous wording of many of its provisions—such as the Second Amendment’s right “to keep and bear arms” and the Eighth Amendment’s prohibition of “cruel and unusual punishments”—has been a source of constitutional controversy and intense political debate. Further, the rights guaranteed are not absolute, and there has been considerable disagreement about the extent to which they limit governmental authority. The Bill of Rights originally protected citizens only from the national government. For example, although the Constitution prohibited the establishment of an official religion at the national level, the official state-supported religion of Massachusetts was Congregationalism until 1833. Thus, individual citizens had to look to state constitutions for protection of their rights against state governments.

The Fourteenth Amendment

After the American Civil War, three new constitutional amendments were adopted: the Thirteenth (1865), which abolished slavery; the Fourteenth (1868), which granted citizenship to those who had been enslaved; and the Fifteenth (1870), which guaranteed formerly enslaved men the right to vote. The Fourteenth Amendment placed an important federal limitation on the states by forbidding them to deny to any person “life, liberty, or property, without due process of law” and guaranteeing every person within a state’s jurisdiction “the equal protection of its laws.” Later interpretations by the Supreme Court in the 20th century gave these two clauses added significance. In Gitlow v. New York (1925), the due process clause was interpreted by the Supreme Court to broaden the applicability of the Bill of Rights’ protection of speech to the states, holding both levels of government to the same constitutional standard. During subsequent decades, the Supreme Court selectively applied the due process clause to protect from state infringement other rights and liberties guaranteed in the Bill of Rights, a process known as “selective incorporation.” Those rights and liberties included freedom of religion and of the press and the right to a fair trial, including the right to an impartial judge and to the assistance of counsel. Most controversial were the Supreme Court’s use of the due process clause to ground an implicit right of privacy in Roe v. Wade (1973), which led to the nationwide legalization of abortion, and its selective incorporation of the Second Amendment’s right to “keep and bear Arms” in McDonald v. Chicago (2010).

The Supreme Court applied the equal protection clause of the Fourteenth Amendment in its landmark decision in Brown v. Board of Education of Topeka (1954), in which it ruled that racial segregation in public schools was unconstitutional. In the 1960s and ’70s the equal protection clause was used by the Supreme Court to extend protections to other areas, including zoning laws, voting rights, and gender discrimination. The broad interpretation of this clause has also caused considerable controversy.

The Constitution as a living document

Twenty-seven amendments have been added to the Constitution since 1789. In addition to those mentioned above, other far-reaching amendments include the Sixteenth (1913), which allowed Congress to impose an income tax; the Seventeenth (1913), which provided for direct election of senators; the Nineteenth (1920), which mandated women’s suffrage; and the Twenty-sixth (1971), which granted suffrage to citizens 18 years of age and older.

In more than two centuries of operation, the United States Constitution has proved itself a dynamic document. It has served as a model for other countries, its provisions being widely imitated in national constitutions throughout the world. Although the Constitution’s brevity and ambiguity have sometimes led to serious disputes about its meaning, they also have made it adaptable to changing historical circumstances and ensured its relevance in ages far removed from the one in which it was written.

President Lyndon B. Johnson (Lyndon Johnson) signs the 1964 Civil Rights Act as Martin Luther King, Jr., others look on East Room, White House, Washington, D.C., July 2, 1964.
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