28 U.S.C. § 144 : US Code - Section 144: Bias or prejudice of judge

      Whenever a party to any proceeding in a district court makes and
    files a timely and sufficient affidavit that the judge before whom
    the matter is pending has a personal bias or prejudice either
    against him or in favor of any adverse party, such judge shall
    proceed no further therein, but another judge shall be assigned to
    hear such proceeding.
      The affidavit shall state the facts and the reasons for the
    belief that bias or prejudice exists, and shall be filed not less
    than ten days before the beginning of the term at which the
    proceeding is to be heard, or good cause shall be shown for failure
    to file it within such time. A party may file only one such
    affidavit in any case. It shall be accompanied by a certificate of
    counsel of record stating that it is made in good faith.