Patrick DeLeon, chief of staff to U.S. Sen. Daniel K. Inouye in Washington, D.C., is retiring.

DeLeon has been an aide to the Hawaii Democrat since Inouye served on the committee investigating the Watergate scandal in 1973. A clinical psychologist, DeLeon also served as president of the American Psychological Association.

Marie Blanco, the deputy chief of staff, will replace DeLeon.

Inouye, in a statement Tuesday, recognized DeLeon for his service and friendship.

“Under his service, the importance of nurses, psychologists, and other health professionals was properly recognized,” Inouye said. “He has been at the forefront of shepherding legislation related to Native Hawaiians, immigrant children, the people of the Pacific, and higher education.

“He has been very active in helping our community college system become full fledged, four-year colleges. For example, he played a major role in the establishment of the school of pharmacy and the school of nursing at the University of Hawaii’s Hilo campus.”