Tribal Acknowledgment and Indian Bureau Enhancement Act of 2003

Tribal Acknowledgment and Indian Bureau Enhancement Act of 2003 - Requires any Indian group in the continental United States that desires to be acknowledged as an Indian tribe to submit to the Secretary of the Interior a letter of intent in advance of or with its documented petition to substantiate claims of continuous existence as an Indian tribe.

Requires the Secretary to: (1) publish at least every three years a list of all Indian tribes entitled to receive services from the Bureau of Indian Affairs; (2) make guidelines available for, and provide advice on, the preparation of documented petitions; and (3) consider the criteria for acknowledgment to be met upon determining that it is more likely than not that the evidence presented demonstrates that the petitioner has met each mandatory criterion.

Specifies the requirements of a petition for acknowledgment.

Sets forth the mandatory criteria for Federal acknowledgment, including evidence that: (1) the group has been identified as an American Indian group on a substantially continuous basis since 1900; (2) a predominant portion of the group has composed a distinct community throughout the historical period; and (3) the petitioner has maintained political influence and authority over its members as an autonomous entity throughout the historical period.