WASHINGTON — The Air Force has found no evidence to corroborate allegations of sexual misconduct by the four-star nominated to be the military’s No. 2 officer, but that investigation may not be enough to satisfy Senate lawmakers considering his nomination.

On April 12, a service member came forward with allegations that U.S. Strategic Command head Gen. John Hyten, currently the head of U.S. Strategic Command, initiated “abusive sexual contact” and “an inappropriate relationship” with her, a senior military official familiar with the investigation told reporters Wednesday.

Hyten, announced in April as the nominee to become vice chairman of the Joint Chiefs of Staff, is awaiting confirmation by the Senate Armed Services Committee, whose members were briefed Wednesday on the investigation carried out by the Air Force Office of Special Investigation.

“After a comprehensive investigation by the Air Force Office of Special Investigations, there was insufficient evidence to support any finding of misconduct on the part of Gen. Hyten,” said Pentagon spokeswoman Col. DeDe Halfhill. “Gen. Hyten cooperated with the investigation. With more than 38 years of service to our nation, Gen. Hyten has proven himself to be a principled and dedicated patriot.”

According to the senior military official, Air Force OSI presented a report to a court-martial convening authority based on an “exhaustive” investigation where the office interviewed 53 witnesses across three countries and 13 states. That authority — Gen. Mike Holmes, head of Air Combat Command — and his legal counsel found insufficient evidence to bring criminal charges against Hyten or to recommend administrative actions.

The allegations comprise a total of nine incidents occurring between February 2017 and February 2018, including accusations of unwanted kissing and touching. News of the complaints against Hyten were first reported by Defense One.

But Air Force OSI’s investigation, which involved speaking to staff close to Hyten and the accuser and reviewing “thousands” of emails, produced no evidence that the events occurred. The investigation is considered officially closed.

“We’re just out of rocks to turn over,” the senior military official said.

Until today’s revelations, it had been expected that Hyten would face little opposition on the Hill. As STRATCOM head, he is a regular visitor to Congress, and has frequently drawn praise during hearings for his work on space and nuclear issues.

Gen. Paul Selva, who has served as vice chairman since 2015, is scheduled to retire on July 30. Should Hyten’s nomination be held up, it would create yet one more empty spot in Pentagon leadership. Among the other jobs that are currently being filled in an acting capacity: secretary of defense, deputy secretary of defense, chief management officer, and secretary of the Air Force.

That confusion will only grow following the formal nomination of acting Defense Secretary Mark Esper to the fully confirmed secretary role; with that nomination comes a shuffle that will require Esper to step down and resume working as secretary of the Army, while Navy Secretary Richard Spencer takes over as acting SecDef.

Aaron Mehta in Washington contributed to this report.

Valerie Insinna is Defense News' air warfare reporter. She previously worked the Navy/congressional beats for Defense Daily, which followed almost three years as a staff writer for National Defense Magazine. Prior to that, she worked as an editorial assistant for the Tokyo Shimbun’s Washington bureau.

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