Federal agencies administering the Endangered Species Act often issue justifications for their actions that are filled with badly flawed or even fabricated data, according to a congressional report being released today.

“Many reports and studies used to justify ESA decisions have been found to have mathematical errors, missing data, errors of omission, biased sampling, undocumented methods, simulated data in place of more accurate empirical data, discrepancies between reported results and data, inaccurate mapping, selective use of data, subjective interpretation of results, fabricated data substituted for missing data, and even no data at all,” according to the report of the 13-member ESA Working Group in the House of Representatives.

A related problem, according to the report, is that “most of the federal agencies that administer ESA are unable to make basic and legitimate data” underlying their policies and procedures available to the public, as required by law.

As a result, “the Obama administration is more frequently resorting to the use of executive orders and closed-door settlements on ESA,” the report said.

Closed-door settlements are imposed by courts to settle cases often involving environmental activists suing a federal agency, seeking to force the agency to take a particular action.

The ESA — approved in 1973 — is the main federal law designed to protect endangered species from manmade threats.

The recent revival of the bald eagle population across America after it nearly became extinct in the 1980s is likely the law’s best-known success.

The group has been taking testimony and reviewing a variety of assessments by outside experts on the work of the Department of the Interior’s Fish and Wildlife Service and the National Oceanic and Atmospheric Administration’s National Marine Fisheries Service, the two federal agencies most concerned with ESA policy and enforcement.

Rep. Doc Hastings, R-Wash., and Rep. Cynthia Lummis, R-Wyo., lead the group. Hastings is chairman of the House Committee on Natural Resources. Lummis is a member of that committee and vice-chairwoman of the Congressional Western Caucus.

The report pointed to a decision last year in which the U.S. Court of Appeals for the Fourth Circuit ruled that a massive NMFS opinion “relied on a selection of data, tests and standards that did not always appear to be logical, obvious or even rational.”

The NMFS report was prepared for officials of the Environmental Protection Agency considering whether to ban or heavily regulate use of certain pesticides in order to protect salmon in the Pacific.

In another case, the FWS issued a decision in 2010 that relied upon a tax-funded study that was cited more than 60 times as justification for increased government regulation of private lands that are habitat for the Greater Sage-Grouse.

“Yet, the data used in the Garton study still has not been made publicly available. Another scientist’s written requests for the data have been refused,” the report said.

State and local authorities also often have difficulty obtaining the data or scientific studies underlying ESA decisions and policies.

The report said a group of Colorado counties questioned the accuracy of a FWS map to be used in determining sage grouse habitats in the state and asked to see the supporting data: “In more than one case, a court order has been required to obtain the data from federal officials, even though the data was obtained through taxpayer-funded studies.”

Hastings, Lummis and other members of the working group will discuss the report today in a morning news conference on Capitol Hill.

Other issues covered in the report include the growing use of litigation by activists to force federal actions, the dramatic increase in species listed, reforms designed to return ESA to efforts to help endangered species recover sufficiently to be removed from protected status and ensuring transparency and accountability in the measure’s administration by federal officials.

The report’s authors said “litigation and threats of litigation on both substantive and procedural grounds have significantly increased in recent years, and legitimate questions are being raised over petitions, listings, the rigid timeframes, and transparency of data supporting decisions regarding the priorities of the two agencies that administer ESA.”

The litigation has become so frequent that “the exact amount spent by American taxpayers on ESA litigation and attorneys’ fees is unattainable,” the report said. “Even the former Interior Secretary acknowledged at a 2012 budget hearing that he could not identify how much money his agency spent on ESA-related litigation.”

The ESA has not been amended by Congress since 1988. Only 2 percent of all species added to the endangered list since 1973 have recovered sufficiently to be removed.

The working group's report can be read here.

Mark Tapscott is executive editor of the Washington Examiner.