The United States Constitution does not specify qualifications for Justices such as age, education, profession, or native-born citizenship. A Justice does not have to be a lawyer or a law school graduate, but all Justices have been trained in the law. Many of the 18th and 19th century Justices studied law under a mentor because there were few law schools in the country.

It is clear that the U.S.Constitution is completely silent as to qualifications for Supreme Court Justices. However, several preferred qualifications have emerged over the long history of the court. Most Justices tend to begin their tenure while in their 40s or 50s and may remain with the court as long as they wish or until they are impeached for improper behavior. Most Supreme Court nominees are personal acquaintances of the sitting President. An overwhelming majority of them attended law school and worked as a lawyer or served as a judge prior to their nomination. Many of the Justices have held some kind of public office before being confirmed. It is the job of the President to nominate a suitable candidate; the Senate must vote to confirm the candidate that has been nominated. When the Senate does not vote in favor of a candidate, the President must supply another nominee.

More Info: www.supremecourt.gov