MDMA has been banned by the federal government since 1985 as a dangerous recreational drug with no medical value. But interest is rising in its potential to help people suffering from psychiatric or emotional problems. A loose-knit underground community of psychologists, counselors and healers has been administering the drug to patients — an act that could cost them their careers. “I do what is morally right,” said the therapist, who lives in Northern California and did not want to be identified. “If I have the tools to help, it is my responsibility to help.” A series of clinical trials approved by federal drug authorities is now underway to see if the drug’s ability to strip away defensiveness and increase trust can boost the effectiveness of psychotherapy. One of the key studies focuses on MDMA’s effect on military veterans suffering from post-traumatic stress disorder. Farris Tuma, head of traumatic stress research at the National Institute of Mental Health, said he’s skeptical because there is no plausible theory so far about how the drug’s biochemical effects on the brain could improve therapy. “They’re a long way between where they are now and this becoming a standard clinical practice,” he said. A surge in Ecstasy-related deaths at raves has reinforced the compound’s destructive reputation. But some of those who have given MDMA to patients are optimistic. The therapist said she became a believer in the late 1980s after it helped her deal with her own trauma. She has since conducted roughly 1,500 sessions with patients, leading them on four-hour explorations of their feelings.