A portion of a statute that provides that the law is not applicable in certain circumstances due to preexisting facts.

Grandfather clauses, which were originally intended to prevent black people from voting, were named for provisions adopted by the constitutions of some states. Such amendments sought to interfere with an individual's right to vote by setting forth difficult requirements. For example, common requirements were ownership of a large amount of land or the ability to read and write portions of the state and federal constitutions. The name grandfather clause arose from the exceptions that were made for veterans of the Civil War. If the veterans were qualified to vote prior to 1866, their descendants were also qualified. Thus, in effect, if a person's grandfather could vote, he could vote without further restrictions.

These statutes accomplished precisely what was intended, since nearly all slaves and their...