General John R. Allen has been cleared of misconduct by the Pentagon for more than 3,000 emails exchanged with Florida socialite Jill Kelley and revealed during David Petraeus scandal.
John Allen’s nomination to head NATO commander in Europe had been put on hold amid reports the emails were inappropriate.
He is due to relinquish command of his Afghanistan post in February.
Harassment complaints by Jill Kelley led the FBI to unmask an affair between CIA Director David Petraeus and his biographer, Paula Broadwell. He later resigned.
Defence officials told the Associated Press that the White House had not decided whether to go forward with General John Allen’s nomination to Supreme Allied Commander in Europe.
Pentagon spokesman George Little said the defence department “was pleased to learn that allegations of professional misconduct were not substantiated”, adding that defence secretary Leon Panetta had “complete confidence in the continued leadership” of Gen. John Allen.
The emails first came to light as part of a wider investigation into email harassment against Jill Kelley, who knew both Gen. John Allen and David Petraeus, a former general, through social contacts on the Florida army base where US Central Command is headquartered.
When the FBI investigated, it traced the emails to David Petraeus biographer Paula Broadwell, bringing to light her affair with the CIA chief.
Earlier reports suggested Gen. John Allen and exchanged thousands of emails, some described as inappropriate and flirtatious, with Jill Kelley.
The Afghanistan commander had also written a letter to a judge in support of Natalie Khawam, Jill Kelley’s twin sister, in a messy custody dispute.
After being contacted by the FBI, Leon Panetta announced the inquiry into Gen. John Allen and put the commander’s nomination on hold.
Defence officials told the Washington Post that the full investigation had shown that there were in fact only several hundred emails exchanged between the two, mostly notes on current news topics, social invites or compliments on Gen. John Allen’s television interviews.
“Some of the messages are not the sort of things you would print in a family newspaper,” the official said.
“But that doesn’t mean he violated military regulations by sending and receiving them.”
In addition to the inquiry into Gen. John Allen, Leon Panetta asked the Joint Chiefs of Staff to review ethics training after a series of misconduct cases.
General Martin Dempsey, chairman of the Joint Chiefs, has not released the results of his review but has said he found that ethics training for senior leaders should begin earlier in an officer’s career and be reinforced more frequently.david petraeus, jill kelley, john r allen, leon panetta, professional misconduct