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                                                                    EXHIBIT 31.1

                                 CERTIFICATION

I, Robert R. Bennett, certify that:

1.  I have reviewed this annual report on Form 10-K of Liberty Media
    Corporation;

2.  Based on my knowledge, this annual report does not contain any untrue
    statement of a material fact or omit to state a material fact necessary to
    make the statements made, in light of the circumstances under which such
    statements were made, not misleading with respect to the period covered by
    this annual report;

3.  Based on my knowledge, the financial statements and other financial
    information included in this annual report fairly present in all material
    respects the financial condition, results of operations and cash flows of
    the registrant as of, and for, the periods presented in this annual report;

4.  The registrant's other certifying officers and I are responsible for
    establishing and maintaining disclosure controls and procedures (as defined
    in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over
    financial reporting (as defined in Exchange Act Rules 13a-15(f) and
    15d-15(f)) for the registrant and we have:

    a)  designed such disclosure controls and procedures, or caused such
       disclosure controls and procedures to be designed under our supervision,
       to ensure that material information relating to the registrant, including
       its consolidated subsidiaries, is made known to us by others within those
       entities, particularly during the period in which this annual report is
       being prepared;

    b)  designed such internal control over financial reporting, or caused such
       internal control over financial reporting to be designed under our
       supervision, to provide reasonable assurance regarding the reliability of
       financial reporting and the preparation of financial statements for
       external purposes in accordance with generally accepted accounting
       principles;

    c)  evaluated the effectiveness of the registrant's disclosure controls and
       procedures and presented in this annual report our conclusions about the
       effectiveness of the disclosure controls and procedures as of the end of
       the period covered by this annual report based on such evaluation; and

    d)  disclosed in this annual report any change in the registrant's internal
       control over financial reporting that occurred during the registrant's
       most recent fiscal quarter (the registrant's fourth fiscal quarter in the
       case of an annual report) that has materially affected, or is reasonably
       likely to materially affect, the registrant's internal control over
       financial reporting; and

5.  The registrant's other certifying officers and I have disclosed, based on
    our most recent evaluation of internal control over financial reporting, to
    the registrant's auditors and the audit committee of the registrant's board
    of directors (or persons performing the equivalent function):

    a)  all significant deficiencies and material weaknesses in the design or
       operation of internal control over financial reporting which are
       reasonably likely to adversely affect the registrant's ability to record,
       process, summarize and report financial information; and

    b)  any fraud, whether or not material, that involves management or other
       employees who have a significant role in the registrant's internal
       control over financial reporting.

Date: March 15, 2005

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/s/ ROBERT R. BENNETT
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Robert R. Bennett
President and Chief Executive Officer
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