Fourteenth Amendment to the Constitution of the United States forbids the states to deny any citizen the rights granted by federal law. It also defines how citizenship is acquired and declares that all citizens are entitled to equal protection of the law. The original purpose of the amendment was to provide citizenship for former slaves and give them full civil rights. Amendment 14 took effect on July 9, 1868. Through the years, the Supreme Court has interpreted the 14th Amendment in different ways. In 1971, the court declared in Reed v. Reed that no person may be denied equality before the law because of sex.