WASHINGTON (CNN) -- A Navy admiral engaged in sexual relations in the White House in 1990 with a federal employee whom he falsely told he was a widower, according to a report released Friday by the Defense Department.

Rear Adm. John Stufflebeem was demoted and fired from his post as director of the Navy staff.

In March, when the report was submitted to Pentagon officials, Rear Adm. John Stufflebeem was demoted and fired from his post as director of the Navy staff.

Stufflebeem told investigators he couldn't remember the name of the woman he had an affair with. He also lied when he told investigators he did not engage in sexual relations with the woman, identified as "Jane Doe," the Defense Department's inspector general's report said.

Jane Doe, who was then unmarried and working for a federal agency, told the investigators the allegations were true, the report said. Her supervisor and Stufflebeem's superiors supported her testimony.

Stufflebeem was convicted April 18 of making false official statements to investigators. After the hearing, called an admiral's mast, he requested retirement.

Jane Doe told investigators that she and Stufflebeem began their affair on an overseas trip in 1989, that the married admiral told her he was a widower who was raising his children as a single parent and that they had sexual relations several times, including once in a White House room reserved for "military aides with overnight duties."

She also told investigators that Stufflebeem came to her home on the day in August 1990 when she learned he was married and that she called him "scum," shut the door in his face and never spoke to him again. Read the report (PDF)

"We found Ms. Doe to be an extremely credible, candid and articulate witness who willingly participated in our interview with the knowledge and support of her husband," the report said.

By contrast, the report said, Stufflebeem's testimony was "inconsistent with the weight of the evidence," and "it did not appear Stufflebeem's misstatements in these areas of testimony were inadvertent."

At issue was Stufflebeem's removal from his post as a presidential aide in 1990. Stufflebeem testified that he initiated the request to leave his White House post because of "close family personal problems." But his superiors testified that he was removed from the post because of his relationship with the woman -- and that he admitted the affair.

Jane Doe's supervisor told investigators that when she learned of the affair from Doe, she confirmed Stufflebeem's marital status and told Doe what she'd learned.

"Ms. Doe's reaction, according to the supervisor, was one of complete surprise and shock," the report said.

The supervisor also said that she telephoned Stufflebeem's immediate supervisor to tell him of the affair and that when she called a few weeks later to follow up, the supervisor told her that "everybody in town knew Boomer was f'ing some bimbo at the [federal agency]."

Stufflebeem, however, denied to investigators that he had a sexual relationship with Jane Doe, although he admitted to one kiss and said he had an "inappropriate relationship" with her because he told her about his marital problems.

"I did not have sex with this woman," he said during one of two interviews with investigators.

Although he told investigators he could not remember the woman's name, he testified that he "had to live with shame for a long time" after the "inappropriate relationship" ended, that he was "racked with guilt" and "had a terrible time getting myself right with my family."

"So I have had a great 18-year career since I left the White House," he said, according to the report. "If this is the end of it, then I still leave a rewarded individual, thankful for the blessings that I have had."

Investigators found Stufflebeem's remarks inconsistent.

"In our view, comments regarding guilt, shame, and the end of a distinguished naval career are incongruous with a physical relationship limited to one kiss," they wrote in the report.

This year, according to the report, the inspector general's office provided Stufflebeem with its preliminary findings: that he'd provided "false and misleading testimony" regarding the nature of his relationship with Jane Doe, his inability to recall her name and his representation to her of himself as a widower.

Stufflebeem responded with a vehement denial.

"[I] find it extremely regrettable, in a case that has such far reaching implications for my career, that you have chosen to question my integrity," he wrote in a February 15 letter. "The unfortunate truth in this case is that, as a result of lack of evidence to substantiate the allegation of a sexual relationship and in lieu of investigating the underlying allegations, you have chosen to accuse me of being untruthful as I defended myself against these allegations."

Stufflebeem further castigated the investigators because, at that time, they had chosen not to interview Jane Doe "in deference to Ms. Doe's privacy," according to the report. Doe "readily agreed" to testify when they contacted her after Stufflebeem's rebuttal.

"Ms. Doe confirmed that she and Stufflebeem had an extensive physical relationship which began on an overseas trip and lasted intermittently for approximately eight months," the investigators wrote. "The relationship included sexual intercourse on approximately one dozen occasions, to include intercourse during overseas travel, in the White House and in her home."

Doe also said Stufflebeem told her that his wife had died of breast cancer, that a woman who answered the phone when she called his home was the children's nanny and that he continued to wear his wedding ring "for his daughters who missed their late mother."

According to the report, the investigation began when investigators received an anonymous letter containing "significant" details about the affair. Investigators had received another such letter in 1999, but it contained no detail and was not investigated.

Stufflebeem became well known in the initial months of the war in Afghanistan, when he often conducted on-camera television briefings as a Pentagon spokesman. He was then deputy director for global operations on the Joint Staff.

He was commander of the 6th Fleet from May 2005 to September 2007. During that time, he was deputy commander of Naval Forces Europe, joint force maritime component commander in Europe, commander of strike and support forces for NATO, and allied commander with Joint Command Lisbon.

CNN Senior Pentagon Correspondent Jamie McIntyre contributed to this report.

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