Constitutional law relates to the study, practice, interpretation and administration of laws set forth by a country’s constitution. In the US, for example, the US Constitution is the basis for all constitutional law. Any legal subjects that deal with constitutional rights or violations are a part of this field.
Experts in constitutional law may participate in cases that seem to be in clear violation of the constitution. Additionally, such experts may also participate in lobbying to change or amend existing laws if they seem to conflict with a nation’s views. Generally, cases involving the US Constitution are heard by the US Supreme Court. The justices then write opinions or judgments based on their interpretation of the law.
In the US, efforts to change the Constitution are often met with resistance or alternately with support. For example, it has been suggested that the Constitution be changed to more clearly define marriage as between a man and a woman. Activists who wish homosexuals to be able to marry find this a clear violation of their rights. Those opposed to gay marriage support the change in the wording of the law.
Though it would seem that constitutional law is a static field, it is clearly not so, evidenced by this example. In fact, the law is flexible and the US Constitution has undergone many changes and amendments. Initially, the document had seven articles, with further changes or additions being called amendments. The articles are still listed, but since the ratification of the US Constitution, 27 amendments have been added. The most recent amendment was the 27th Amendment, added in 1992, limiting pay raises for members of Congress.
Since the initial writing of the constitution, however, over 10,000 amendments have been proposed. As such, constitutional law and its interpretation are constantly subject to scrutiny. It is possible, though difficult, to amend the Constitution. Some landmark amendments to the Constitution that have changed the way the US administers the law are the 13th Amendment, which abolished slavery, and the 26th Amendment, which made it illegal to stop anyone over 18 from voting.
Since the full text of each article and further amendments are written in terms that are frequently subject to interpretation, the way in which the Constitution is administered can be swayed by the politics of each US Supreme Court Justice. In general, Republican justices tend to more conservatively view constitutional law. Democratic justices are likely to take a more liberal view.
This is not always the case, however, and sometimes, a Supreme Court justice will draft opinions on laws that are not in keeping with the politics of the president who appointed him or her. Justices spend a great deal of time studying the law, and opinions can change over time. Especially since a Supreme Court justice has a lifetime appointment, it is not unusual for a gradual shift in interpretations of constitutional law to occur.