The 20-year-old Maryland Commission on Medical Discipline is charged under the state charter with protecting the public from doctors who are medically incompetent, morally unfit or physically or mentally impaired.

Nine of the 11 members of the commission are physicians -- seven chosen or nominated by the state medical society. The governor and the secretary of the state Department of Health and Mental Hygiene appoint some of the commissioners. All members serve for three-year terms and meet on a volunteer basis two to three times a month.

Complaints about doctors get to the commission's attention through patients, hospitals, doctors, law enforcement officials and occasionally the news media. In addition, the state Health Claims Arbitration Office, which acts as a court for malpractice cases, informs the commission when a malpractice suit is filed.

Complaints include allegations of incompetence or substandard care, dishonesty, substance abuse, psychological problems, immoral conduct and patient abandonment. Many of the complaints accuse doctors of charging excessive fees. The commission can make findings that a doctor is incompetent or has otherwise violated the state Medical Practice Act.

There is a range of disciplinary actions that the commission can take against a physician, including: informal, confidential admonishment; reprimand; probationary status, with conditions that may limit his or her practice; and license suspension or revocation. The commission has the authority to subpoena a doctor's medical and office records.

Under Maryland law, the commission has wide latitude in determining which of those penalties to set. There are no mandatory sanctions for violating specific provisions of the Medical Practice Act. Findings of a violation can be appealed in court.

The commission took over the job of disciplining doctors in 1968 from the state medical society, the Medical and Chirurgical Faculty of Maryland. The commission's counterpart in Washington is the D.C. Commission on the Healing Arts, and in Virginia, the State Board of Medicine.

The physician members of the Maryland commission are Hilary T. O'Herlihy, chairman; Ronald J. Taylor, vice chairman; Rose Mary Bonsack; Michael Dobridge; Claude Hill; Robert Kindred; Reynaldo Lee-Llacer; Karl H. Weaver; and Edilberto Beltran. The two lay members are Christine Moore and Margaret McKean.

There are ways a physician can be prevented from practicing, permanently or temporarily, besides losing his license as a result of action by the commission.

Over the past two decades, 17 doctors have voluntarily surrendered their Maryland licenses rather than face disciplinary charges. Some of those doctors were able to obtain licenses in other states. But that legal loophole has largely been resolved in the past few years as a result of better reporting and dissemination of such data by the Federation of State Medical Boards, a national clearinghouse.

A doctor can also be put out of business in Maryland by the state Board of Medical Examiners, which issues medical licenses and renews licenses every two years. In fiscal 1987, the Board of Medical Examiners refused to renew five licenses, most because false information was included on the renewal application.

The medical society can also prevent a doctor from practicing temporarily if it receives a complaint and determines that the doctor is addicted to drugs or alcohol. The Medical and Chirurgical Faculty can then push the doctor to join its impaired-physician program by threatening to report him to the commission if he fails to do so.

Physicians who join the program generally agree to suspend their practices for periods ranging from 30 days to two years. Medical society Executive Director Angelo Troisi said 18 drug- or alcohol-addicted doctors signed a contract with the society last year agreeing to enter the program.