Supreme Court Chief Justice William Rehnquist is in the hospital being treated for thyroid cancer. In a statement, the court says the 80-year-old spent the weekend in Bethesda Naval Hospital and had a tracheotomy on Saturday. Justices are not meeting this week. Rehnquist is expected back on the bench when the court returns to work next week. He has had a series of health problems. In 2002, he missed several sessions after hurting his knee in a fall. Rehnquist was appointed to the court by President Nixon.