Chief Justice William Rehnquist in December 2003
07/14/2005 AT 10:00 AM EDT
Chief Justice William H. Rehnquist, ailing with cancer and running a fever, was taken by ambulance to Virginia Hospital Center in Arlington, Va., on Tuesday night and was admitted for observation and tests, according to Supreme Court spokeswoman Kathy Arberg.
"We wish him a speedy recovery," President Bush's spokesman, Scott McClellan, said of the 80-year-old, according to reports.
Fueled by the recent retirement of Justice Sandra Day O'Connor, Rehnquist's future has been the subject of intense speculation since he announced in October that he had thyroid cancer. He has said very little publicly about his prognosis and nothing about his future at the court.
In 1986, President Ronald Reagan nominated Rehnquist to replace retiring Chief Justice Warren Burger, over protests at the time by those who labeled Rehnquist a conservative extremist.
There were also charges that he had mishandled a family trust. The accusations remained unproved, however, and the Senate confirmed Rehnquist by a solid majority.