Psychologist Dennis M. Harrison, whose court testimony on behalf of clients in child custody cases gained him a national reputation and a high profile on television interview shows, is embroiled in a legal battle in Howard County to salvage that reputation.

The Columbia clinician's license was revoked in Maryland last week when the state Board of Examiners of Psychologists ruled that he had engaged in unethical and unprofessional conduct with five clients dating back to 1986.

The board ruled that, among other things, Harrison violated confidentiality requirements, misrepresented his doctorate as being in psychology when it was in human development, and in one case allowed a high school student to handle treatment sessions.

Harrison, 43, whose clients have included Elizabeth Morgan in a well-publicized and lengthy custody case, has denied all the charges.

"He's in trouble because he's extremely vocal and active in child abuse cases," Harrison's attorney, Jeffrey Thompson, said yesterday.

Thompson said in a statement that the board's action "strikes a blow to the rights of abused children and those doctors who speak out for them."

Harrison's work with Morgan in her child custody battle with her ex-husband, Eric Foretich, was not among the five cases cited by the licensing board, nor was his arrest a year ago in St. Mary's County, Md., on a conspiracy charge -- later dropped -- in the kidnapping of a child in a custody case.

Harrison is licensed to practice in the District of Columbia, and continues to work as a consultant, Thompson said, adding, "I don't know if he is treating patients." Thompson was in Howard County Circuit Court yesterday seeking to block the license revocation order.

Harrison has said that he has testified in custody and child sexual abuse cases in 37 states since 1986, when he began to focus his practice on forensic work.

Harrison was cited by the Maryland board for allegedly violating confidentiality when he showed photographs and part of a videotape on the TV show, "A Current Affair," of a child he interviewed while she was in hiding from her father.

The board said Harrison also had his assistant, then a high school student, substitute for him in sessions with a client who was on probation for a child pornography conviction.