U.S. Magistrate Jean F. Dwyer, in a highly unusual move, wrote a letter to a D.C. Superior Court judge requesting that the judge be lenient in sentencing a lawyer who had pleaded guilty to a charge of sodomy with a juvenile.

The case involved Roger H. Moore, who, after being convicted in Arlington Circuit Court of fondling a 13-year-old boy he was appointed to represent, pleaded guilty in D.C. Superior Court to sodomy with the 17-year-old brother of a client. Dwyer had no role in either case.

In a letter dated Nov. 17, written at the request of Moore's attorney and included in the court records, Dwyer wrote that she had known Moore for several years and that he had "appeared before me on a number of occasions, before his present unhappy involvement."

"I always found him dependable, consciencious, and capable in every way. Without attempting to minimize the gravity of the charges, I hope it will be possible for you to temper justice with mercy in this instance, especially in light of his situation in Virginia," she wrote.

Moore's lawyer, R. Kenneth Mundy, said yesterday that the letter was a "character reference," one of several such documents he said he submitted to the court as part of a request that Superior Court Judge Annice Wagner not impose an additional lengthy sentence on Moore, who is serving a four-year sentence in Virginia on the Arlington conviction.

The Code of Judicial Conduct, the rules issued by the U.S. Judicial Conference to which judges and magistrates are expected to adhere, says that they "should not testify voluntarily as a character witness."

The code explains that "testimony of a judge as a character witness injects the prestige of his office into the proceeding in which he testifies and may be misunderstood to be an official testimonial." Dwyer did not testify in court.

In an interview yesterday, Dwyer said she did not regard the letter as a character letter. "That was very carefully worded," she said, adding that she considered it "simply a declaration of his competency as an attorney."

When asked about the request for mercy in the letter, Dwyer said she would not comment further on the letter.

"I certainly would do nothing to attempt to interfere with Judge Wagner's discretion," Dwyer said. "She and I never discussed it, I wouldn't dream of doing that, that would be improper. I declined to testify in person. That would be going too far."

Mundy said the canon on judges testifying as witnesses was a "suggested canon, not mandated."

One knowledgeable federal judge who asked not to be identified disagreed with Mundy's assessment. "That is like talking about the Ten Suggestions," the judge said.

Wagner would not comment on the letter yesterday.

Wagner eventually sentenced Moore to serve one year in prison after he completes his Virginia sentence.

Mundy, who said Wagner could have sentenced Moore to up to 10 years in prison, termed the one-year sentence moderate. Wagner could have required the sentence to be served concurrently with the Virginia sentence, Mundy said, which would have been far more lenient.

Dwyer, who was appointed unanimously last year by the District Court to serve a second eight-year term as a magistrate, said yesterday that she did not know what sentence Moore received.

Dwyer said she did not recall ever having written a similar letter to a judge, although she said she occasionally wrote letters of reference for individuals seeking jobs.

One federal judge said yesterday that such situations occur sometimes because judges and magistrates are often "buried in work, they often forget about the canons, want to do someone a favor and that might be what happened in this case."

A recently passed federal statute authorizes the U.S. Judicial Conference and the various federal circuit judicial councils to investigate complaints about federal judges, who are lifetime appointees and subject to removal only by the U.S. Senate.

Magistrates, who are appointed by local district court judges, also are subject to discipline, such as public censure or reprimand, according to several lawyers familiar with judicial proceedings. There is no explicit mechanism for disciplining judges or magistrates who violate the canons of conduct.

Most complaints involving judges that do not involve alleged criminal conduct are handled privately, these lawyers said.