The US military held WikiLeaks suspect Bradley Manning under strict "suicide watch" partly because his gender identity struggle showed he was mentally "not stable," a witness said.
Manning, a former army intelligence analyst in Iraq, is accused of the biggest intelligence leak in American history for allegedly passing a massive trove of classified documents to Julian Assange's anti-secrecy website.
Manning's purported gender struggle came up at a pre-trial hearing as his defense urged a military judge to dismiss the case, citing alleged "unlawful punishment" endured by the soldier during nine months of solitary confinement.
Master Sergeant Craig Blenis, who served as a counselor at the Quantico military base where the WikiLeaks suspect was detained, said the gender issue "on top of other things" was a factor that determined his detention status.
It "shows he's not stable," Blenis told the court, explaining why Manning was put under stringent "prevention of injury" status at the Virginia base.
The subject of Manning's alter ego, Breanna, first arose in hearings last year. In court documents, the defense argues that prison authorities displayed "intolerance and homophobia" in their treatment of Manning, now aged 24.
Blenis was pressed on why he recommended that the army private remain under harsh, maximum custody despite filing reports that described him as a model detainee and advice of psychiatrists, who said the accused was not suicidal.
In a video presented to the court, Blenis was seen speaking to Manning through prison bars, telling him that he is a trouble-free inmate: "I wish I had a 100 Mannings."
In the video, Manning can be seen standing naked from the waist up, with his arms behind him -- prison authorities forced him to strip at night as part of the prevention of injury (POI) regime.
The defense also confronted Blenis with an email that shows him joking with his commanding officer about a possible birthday package addressed to Manning that the Quantico jail rejected because it had not been cleared in advance.
In the email, Blenis lists the official reasons why the package was refused but added that the decision was taken because they "felt like being" difficult.
Blenis said Manning's reluctance to engage in conversations with troops overseeing his detention caused him concern, particularly because the accused admitted to having suicidal thoughts upon arriving at Quantico in July 2010.
Manning's civilian defense lawyer David Coombs suggested that his client, who was earlier held in US custody in Kuwait, was merely a man of few words.
"Is it possible you're looking at a quiet guy?" asked Coombs.
"That's not what I thought," the sergeant replied.
Manning was held at Quantico until April 2011 before being transferred to a prison at Fort Leavenworth, Kansas, where authorities concluded he was not suicidal and could be held under more lenient conditions.
Legal experts say it is unlikely that Judge Denise Lind will throw out the case because of Manning's detention measures, but she could take the issue into account during sentencing, if the soldier is found guilty as charged.
If convicted on all 22 counts, including a charge of "aiding the enemy," Manning could spend the rest of his life in prison.
His trial has been pushed back to March 2013 instead of February that year, Judge Lind announced earlier.
Due to last about six weeks, the court-martial could begin March 6 or March 18, depending on the pace of legal proceedings, she said.
The pre-trial hearing on Manning's treatment at Quantico, which began last Tuesday, is due to resume on Wednesday.