THOUGH BEST REMEMBERED by many for the headline-making cases he participated in as a Washington Lswyer and Assistant attorney general of the United States, Fred M. Vinson Jr., who died here Sunday at the age of 57, enjoyed a special respect from colleagues who knew and appreciated the time and effort he devoted to the local issues and people of this city. From general court matters to the legal protection of the poor, the education of young students and the self-government efforts of the District, Mr. Vinson was instrumental in galvanizing the support of other lawyers and assisting city officials in their legislative efforts.

As chairman of the board of trustees of the D.C. Public Defender Service, Mr. Vinson was never content to be a figurehead. In addition to long hours spent assisting and encouraging the staff in its casework, he was one of the service's strongest public boosters. His interest in the law also extended to the youth of the area, even during his term in the Justice Department, when he promoted special programs in the junior high schools on "citizenship and the law" that soon became popular in many states.

Less popular at the time -- but no less dear to the heart of Mr. Vinson, who grew up here and graduated from Wilson High School and Washington and Lee University -- was the cause of home rule and full congressional representation for the District. In 1972, he led an attempt to put the American Bar Association's weight behind a D.C. suffrage effort that had won sponsorship by the D.C. Bar Association while he was president of the organization. At the national convention in New Orleans, Mr. Vinson argued that approval of the effort would be consistent with bar policy of working for nonpartisan reform. The measure was tabled, but not so Mr. Vinson's commitment.

There were other projects, too, for the board of trade, for civic organizations and charitable causes and for organizations connected with law, such as the Supreme Court Historical Society. It is for these largely unsung but persistent efforts that Mr. Vinson will be remembered locally as a constant contributor.