WASHINGTON — Elaine McCusker, who has been serving as the Pentagon’s acting comptroller for 18 months, has resigned, Secretary of Defense Mark Esper announced Tuesday.

“Today Elaine McCusker submitted her resignation as Deputy Under Secretary of Defense (Comptroller) effective Friday, June 26, 2020,” Esper said in a statement. “Since joining the Department of Defense, Elaine has worked tirelessly to ensure that our budgeting and audit processes give full value to the taxpayer while meeting the enormous security needs of our nation as well as the men and women who serve it.”

“I am grateful for her dedication to public service and the contributions that she has made to the department and wish her the very best in her future endeavors.”

McCusker was sworn in as deputy undersecretary of defense (comptroller) on Aug. 7, 2017. In that role, and then acting as the full comptroller, she played a critical role in the department’s audit process, as well as the development of the FY20 and FY21 budgets.

Traditionally the comptroller is a little known figure outside of defense budget circles. McCusker, however, became the subject of headlines during the impeachment of President Donald Trump at the start of this year, when emails she sent questioning the legality of the White House holding up weapons funding for Ukraine became part of the argument by Democrats that Trump had broken the law.

Those emails would appear to have cost her the full comptroller’s role, despite support from inside the department for the work she had done.

Despite being the announced nominee for the comptroller job, McCusker never received a hearing in front of the Senate Armed Services Committee. Shortly after the impeachment process wrapped up, the New York Post reported that the White House planned to pull McCusker’s nomination over the Ukraine emails.

Following that report, both DoD officials and SASC chairman Sen. Jim Inhofe, R-Okla., cast doubt on the news. At a Feb. 19 press briefing, Pentagon public affairs head Jonathan Hoffman said McCusker is “still the president’s nominee... I’ve not seen anything additional that would lead me to believe that that is a reality.” And Pentagon sources insisted McCusker remained a strong nominee who has Esper’s trust.

By March 2, however, the White House officially announced that McCusker’s nomination was being withdrawn. It has yet to announce a replacement nominee for the job.