WASHINGTON – Actions by the Justice Department during the Bush administration were inappropriately political, but not criminal, when a U.S. attorney was fired in 2006, prosecutors said Wednesday in closing a two-year investigation without filing charges.

Investigators looked into whether the Bush administration improperly dismissed nine U.S. attorneys, in particular New Mexico U.S. Attorney David Iglesias, as a way to influence criminal cases. The scandal added to mounting criticism that the administration had politicized the Justice Department.

In 2008, the Justice Department assigned Nora Dannehy, a career prosecutor from Connecticut, to investigate the firings.

“Evidence did not demonstrate that any prosecutable criminal offense was committed with regard to the removal of David Iglesias,” the Justice Department said in a letter to lawmakers Wednesday. “The investigative team also determined that the evidence did not warrant expanding the scope of the investigation beyond the removal of Iglesias.”

Dannehy faulted the Justice Department for firing Iglesias without even bothering to figure out whether complaints about him were true. That indicated “an undue sensitivity to politics on the part of DOJ officials who should answer not to partisan politics but to principles of fairness and justice,” the Justice Department wrote in its letter.