Capt. Susan Carlson was not a typical recruit when she volunteered for the Army in 2006 at the age of 50. But the Army desperately needed behavioral health professionals like her, so it signed her up.

Though she was, by her own account, "not a strong soldier," she received excellent job reviews at Fort Leavenworth, Kan., where she counseled prisoners. But last year, Carlson, a social worker, was deployed to Afghanistan with the Colorado National Guard and everything fell apart.

After a soldier complained that she had made sexually suggestive remarks, she was suspended from her counseling duties and sent to an Army psychiatrist for evaluation. His findings were shattering: She had, he said in a report, a personality disorder, a diagnosis that the military has used to discharge thousands of troops. She was sent home.

She disputed the diagnosis, but it was not until months later that she found what seemed powerful ammunition buried in her medical file, portions of which she provided to The . "Her command specifically asks for a diagnosis of a personality disorder," a document signed by the psychiatrist said.

Veterans’ advocates say Carlson stumbled upon evidence of something they had long suspected but had struggled to prove: that military commanders pressure clinicians to issue unwarranted psychiatric diagnoses to get rid of troops.

"Her records suggest an attempt by her commander to influence medical professionals," said Michael J. Wishnie, a professor at Yale Law School and director of its Veterans Legal Services Clinic.

Since 2001, the military has discharged at least 31,000 service members because of personality disorder, a family of disorders broadly characterized by inflexible "maladaptive" behavior that can impair performance and relationships.

For years, veterans’ advocates have said that the Pentagon uses the diagnosis to discharge troops because it considers them troublesome or wants to avoid giving them benefits for service-connected injuries. The military considers personality disorder a pre-existing problem that emerges in youth, and as a result, troops given the diagnosis are often administratively discharged without military retirement pay. Some have even been required to repay enlistment bonuses.

By comparison, a diagnosis of post-traumatic stress disorder is usually linked to military service and leads to a medical discharge accompanied by certain benefits.

In recent weeks, questions about whether the Army manipulates psychiatric diagnoses to save money have been raised at Joint Base Lewis-McChord near Tacoma, Wash., where soldiers undergoing medical evaluations before discharge complained that psychiatrists rescinded PTSD diagnoses, leaving the soldiers with diagnoses like personality disorder that did not qualify them for medical discharges.

In a memorandum, an Army ombudsman wrote that a doctor from the base hospital, Madigan Army Medical Center, said that one diagnosis of post-traumatic stress disorder can cost $1.5 million in benefits over a soldier’s lifetime. The doctor also counseled his colleagues to be good stewards of taxpayer money by not "rubber-stamping" such diagnoses.

In the wake of those complaints, the Army has removed the head of Madigan and suspended two doctors at a special forensic psychiatric unit. It has also reviewed the cases of 14 soldiers and reinstituted PTSD diagnoses for six of them.

Some senior military officials have raised concerns that PTSD is overdiagnosed. Still, the Defense Department has denied that it uses psychiatric diagnoses either to weed out injured or low-performing troops, or to save money.

"Our goal is to provide the most accurate diagnosis," said Maria Tolleson, a spokeswoman for the Army Medical Command.

On Carlson’s case, the Colorado National Guard declined to comment. Officials at Womack Army Medical Center at Fort Bragg, N.C., said the psychiatrist who evaluated Carlson in Afghanistan, Maj. Aniceto Navarro, was not available for an interview.

But in a statement, the hospital said: "No commander may order a credentialed clinician to make a particular diagnosis. Dr. Navarro did not feel he was being ordered by the service member’s command to make a particular diagnosis. The sentence referenced was written in terms of the commander asking to evaluate for a personality disorder, i.e. asking if one existed, not ordering to diagnose a personality disorder."

Though it is impossible to know how many veterans are disputing their personality disorder discharges, Vietnam Veterans of America, an advocacy group, with help from the Yale veterans legal clinic, has sued the Defense Department seeking records they say will show that thousands of troops have been unfairly discharged for personality or adjustment disorder since 2001.

"We believe that many of the people who received personality disorder discharges were wrongly diagnosed and that in fact they were suffering from PTSD or traumatic brain injury," said Thomas Berger, executive director of Vietnam Veterans of America’s health council.

Although the number of personality disorder discharges is small relative to the total number of troops who have served since 2001, Congress was concerned enough about the issue to hold hearings in 2007 after reading reports that troops with post-traumatic stress disorder and other combat-related injuries were being discharged for personality disorder.

The Defense Department then tightened its requirements, partly to ensure that troops who had served in combat zones and had PTSD were not discharged for personality disorder. Personality disorder discharges subsequently declined, to 1,078 in 2010 from 4,264 in 2007, data obtained by Vietnam Veterans of America show.

But the Government Accountability Office said in 2010 that the Defense Department had not proved that it was in full compliance with its rules. And Carlson’s case shows that the military continues to issue personality disorder diagnoses in questionable ways, according to veterans’ advocates and her lawyers, Stephen H. Carpenter Jr. and Daniel C. Russ.

Unlike the soldiers at Madigan, Carlson has not been given a diagnosis of PTSD. But the personality disorder diagnosis could complicate her ability get a medical discharge for a back injury and other problems. Perhaps more significant, the diagnosis will be listed on her discharge papers, which employers typically review when they are considering veterans for a job.

"It may have a significant impact on her ability to find employment," Carpenter said.

Carlson, now 55, signed up with the Army after a co-worker at a Milwaukee trauma hospital, a surgeon in the National Guard, told her that the Army badly needed therapists and social workers. Intrigued, she got an age waiver and joined through a program that commissions officers based on their specialized training.

At Fort Leavenworth, where she served for three years, supervisors called her "highly talented," "outstanding" and "a dedicated officer," according to a 2008 evaluation.

After leaving active duty, Carlson moved to Colorado Springs, Colo., in 2010 to take a civilian job as a substance abuse counselor at Fort Carson. But soon after arriving, she learned that the Colorado National Guard, which she had just joined, would deploy to Afghanistan in early 2011. She told her commander she wanted to go.

"I wanted to experience what soldiers experience," she said in an interview.

Her problems began soon after she arrived in Afghanistan last February. She got lost outside a combat outpost and wore shorts when she should have been in combat uniform. Then a junior enlisted soldier accused her of sexual harassment, citing an off-color remark she made during a game of Scrabble with several soldiers at a combat outpost.

Carlson contends the remark was innocent, but the Army sent her back to Bagram Air Base near Kabul and opened an investigation. A major general eventually gave her a memorandum of reprimand, a potentially career-ending action. But she says it was the psychological evaluation she received at Bagram that upset her the most.

In notes from that evaluation, Navarro wrote that "it is very difficult to draw absolute conclusions for a personality disorder." But he noted that her command had asked for the diagnosis and, in his final report dated three days later, Navarro did just that.

Carlson has "a very dramatic style" and "chronic difficulty in adjusting," Navarro wrote in that report, concluding that she had "personality disorder NOS" — not otherwise specified — "with histrionic traits." He recommended that the Army move swiftly to discharge her if she did not comply with counseling from her commander.

Experts say personality disorder is generally evident in a person’s youth, leaving a telltale pattern across failed jobs and broken relationships. For that reason, they generally recommend that diagnoses include reviews of patients’ medical records and interviews with people who have known them for years. Navarro says in his notes that he did not have access to her records.

Dr. Andrew E. Skodol, research professor of psychiatry at the University of Arizona and an expert on personality disorder who was not familiar with Carlson’s case, said it would not be surprising for a person who entered the Army in middle age to have trouble adapting to the stresses of military life and deployment. But that would not necessarily qualify as a personality disorder, Skodol said.

After leaving Afghanistan last year, Carlson went to Joint Base Lewis-McChord, where a psychiatrist gave her a diagnosis of adjustment disorder, her lawyers said. That psychiatrist has since been suspended as part of the Army’s investigation into Madigan.

It will be up to the Colorado National Guard to decide how Carlson will be discharged, a process that could take months. At the least, Carlson wants the personality disorder diagnosis removed from her record.

"It’s a bad label," she said. "I’m a broken soldier. I’m old. And they just want to get rid of me."