21st Century Endangered Species Transparency Act

Endangered Species Transparency and Reasonableness Act - (Sec. 2) Amends the Endangered Species Act of 1973 to require the Secretary of the Interior or the Secretary of Commerce, as appropriate, to make publicly available on the Internet the best scientific and commercial data available that are the basis for the determination of whether a species is an endangered species or a threatened species, including each proposed regulation for the listing of a species.

Prohibits the appropriate Secretary from making the information publicly available when: (1) the public disclosure of the information is prohibited by a state law requiring the protection of personal information, and (2) the state requests that the information be withheld.

Requires the appropriate Secretary to execute an agreement with the Department of Defense (DOD) that prevents the disclosure of classified information pertaining to DOD personnel, facilities, lands, or waters.

(Sec. 3) Requires the appropriate Secretary to: (1) provide to affected states all data that is used as the basis of a determination on whether a species is an endangered species or a threatened species before making a determination; and (2) use data submitted by a state, tribal, or county government in making such a determination.

(Sec. 4) Requires the Secretary of the Interior to submit an annual report detailing federal expenditures for civil actions brought under the ESA containing claims that are based on the actions of the Department of the Interior, the Forest Service, the National Marine Fisheries Service, the Bonneville Power Administration, the Western Area Power Administration, the Southwestern Power Administration, or the Southeastern Power Administration. Requires Interior to make the information available online in a searchable database.

Requires the report to include the total funds expended to respond to ESA lawsuits, the number of full-time federal employees dedicated to ESA lawsuits, attorneys' fees awarded in the course of ESA lawsuits and settlements, and any federal funding used in bringing a claim under the ESA.

(Sec. 5) Replaces the current standard for awarding court costs, including attorney's fees, in citizen suits with the federal judicial code standard for awarding costs to a prevailing party.

Written by the nonpartisan Congressional Research Service. All summary versions on Congress.gov