WHEN PRESIDENT JOHNSON appointed Harold Leventhal to the U.S. Court of Appeals for the District of Columbia in 1965, we wrote that this intelligent and prolific attorney "will bring learning, sensibility and a richly reflective mind to the bench." That was quite a tall order, but Judge Leventhal, who died here Tuesday at the age of 64, delivered in full.Not only did he exercise his exceptional talents vigorously, he also coupled his leadership with a deep concern for individual civil liberties and rights.

Judge Leventhal's varied interests and abilities suited this court perfectly, since it was developing a record as a highly visible, often controversial and far-reaching appellate bench. As a productive contributor who usually was aligned with the more open and legally tolerant wing of this "liberal" court, Judge Leventhal wrote widely on numerous topics, from administrative law -- one of several specialties -- to immigration policies, libel, criminal law and human rights. His scholarly essays and opinions explored and expanded the law -- thoughtfully sharpening definitions of constitutional protections. They included ordering free trial transcripts for indigent defendants, help for businesses uprooted by urban renewal, speedy trials, an end to tax exemptions for racially segregated private schools and sharp curbs on police search and seizure powers and on abuses in the handling of anti-war demonstrators.

These decisions were more than the philosophizing of a brilliant legal mind -- they were the expressions of a warm and witty man with a down-to-earth feeling for people as individuals, as neighbors and as citizens of a democracy. It was these qualities that made Harold Leventhal such a special person and superior judge.