Senate Republicans are aiming to make an issue of President Obama's selection to fill the seat of Justice John Paul Stevens having no prior judicial experience. Elena Kragan is the Solicitor General for the United States and argues before the Supreme Court on issues involving the federal government. Funny that Republicans didn't have a problem with President George W. Bush's selection of Harriet Miers, former White House Counsel, to fill a seat on the bench. But, then, consistency has never been a priority of the two major parties.
Neither former Chief Justice Earl Warren nor Chief Justice William Rehnquist, appointed by Presidents Eisenhower and Nixon respectively, had any prior judicial experience before taking their seats on the high court.
The judicial Power of the United States, shall be vested in one supreme Court, and in such inferior Courts as the Congress may from time to time ordain and establish. -- U.S. Constitution, Art. III, Sec. 1The U.S. Supreme Court was created by Article III of the United States Constitution. Interestingly enough, there is no requirement that a nominee for the Court even be a lawyer.