William H. Webster, director of the Federal Bureau of Investigation, yesterday urged American University graduates to become involved in their communities and to foster American values of participatory democracy.

"Wherever you go, whatever you do, reinforce the sense of community that underpins everything we do at the national level," he told an audience of more than 2,000 at the 12th commencement of the College of Public and International Affairs.

He said terrorism "in the conventional sense" was not active in the United States because of the country's democratic traditions.

He lauded the nation's "spirit of justice that springs upward from communities."

"The trend of participatory democracy, of community service, must be fostered at every level," Webster said in a 10-minute speech.

"Whatever your role in life, the key is participation." Participation in democracy and community, he said, "brings out the best in us. It is, in short, to care."

Webster, who has been head of the FBI since 1978, said, "Private citizens share with careerists the responsibility of governance in a free society." A lawyer and a former judge, he described himself as "a private citizen on loan" to government.

Webster's speech came after a procession of graduates and faculty members filed into Constitution Hall at 18th and D streets NW. Dressed in black robes and festooned with bright-colored academic hoods, they were trailed by a company of bagpipers, their instruments droning.

Webster, 61, who received an honorary doctor of laws degree, addressed one of five commencement ceremonies at the university yesterday.

The university conferred about 1,200 degrees to graduates of the College of Arts and Sciences, the Kogod College of Business Administration, the Washington College of Law and the Lucy Webb Hayes School of Nursing.