[JURIST] AP is reporting that Chief Justice William Rehnquist [Wikipedia profile; JURIST news archive; JURIST essay] has died, according to a US Supreme Court spokeswoman. He was 80 and had been suffering from thyroid cancer; his last high-profile public appearance off the bench was in January this year when he administered the inaugural oath [JURIST video] to President George W. Bush at his second inaugural. He was originally sworn in as an Associate Justice in 1972.

11:35 PM ET – Spokeswoman Kathy Arberg said in a statement that Rehnquist had died Saturday evening at his home in Arlington Virginia surrounded by members of his family. The statement said that he "continued to perform his duties on the court until a precipitous decline in his health the last couple of days." AP has more.

Rehnquist was appointed to the Supreme Court in 1971 by President Nixon and confirmed later that year. He began his judicial career in January of 1972 and became Chief Justice in 1986 under President Reagan [History Channel recorded audio of Reagan remarks at swearing-in ceremony]. Rehnquist was considered the most conservative of Nixon's Supreme Court appointments and the most conservative Supreme Court member until the additions of Justices Antonin Scalia and Clarence Thomas. Rehnquist is one of the few Supreme Court Justices to have been appointed from a career other than being a judge at some other level; he worked as Assistant Attorney General for President Nixon's Office of Legal Counsel before being nominated for the Supreme Court.

In anticipation of Rehnquist's possible retirement, legal scholars gathered at conferences earlier this year to consider his legacy. Watch recorded video of a Hoover Institute panel discussion [transcript] in May 2005. New York Times Supreme Court correspondent Linda Greenhouse addressed [JURIST video] a similar scholarly conference on Rehnquist's jurisprudence at Indiana University Bloomington in April.

President Bush will now have to appoint a second Justice to the Supreme Court, following the prior retirement of Justice Sandra Day O'Connor [JURIST report] and will also need to name a new Chief Justice. Senate confirmation hearings are scheduled to begin next week [JURIST report] for Judge John Roberts, Bush's nomination to replace O'Connor.