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.