A change or addition to a law is called an amendment. Amendments can also be used to change the constitution of a nation. In the United States there have been 27 amendments to the Constitution. The most famous of those are the first ten amendments, which are called the Bill of Rights. Those amendments give specific rights to U.S. citizens.

Constitutional amendments

The U.S. Constitution set up how the U.S. government works. The men who wrote the Constitution believed that it should be changed only if a large majority of people agreed. To change, or amend, the Constitution, two thirds of the members of each house of Congress must approve. When that happens, three fourths of the states must agree to the amendment.

Since the Constitution and the Bill of Rights were written, amendments have passed only 17 times. The 13th Amendment, adopted in 1865, ended slavery. The 15th Amendment (1870) gave the right to vote to men of all races. The 19th Amendment (1920) gave women the right to vote. The 18th Amendment (1919) banned alcohol, but the 21st Amendment (1933) made alcohol legal again. The 22nd Amendment (1951) stated that presidents can be elected to only two terms. The 26th Amendment (1971) gave 18-year-old citizens the right to vote. The 27th Amendment (1992) prevented members of Congress from giving themselves a pay raise while in office.

Some proposed amendments to the Constitution have failed to pass. One of the best known is the Equal Rights Amendment. That failed amendment said that men and women were equal under the law. Congress sent the amendment to the states, but not enough of them approved it. Another failed amendment concerned voting rights in Washington, D.C. That amendment proposed that the nation's capital be represented in Congress, as all states are.

Other types of amendments

As different representatives come and go in Congress, they may decide to change laws that have been passed. One way that they can do that is to add an amendment to the law. States can also amend, or change, their own constitutions. In many states the voters can approve an amendment to the constitution. Amending state constitutions is a much easier process than amending the U.S. Constitution.