Guthman received the Pulitzer in 1950 for a series of Seattle Times articles that cleared a University of Washington professor accused of having communist sympathies.

Guthman died at his home in Los Angeles on Aug. 31 of amyloidosis, the newspaper reported.

Kennedy had Guthman as his press secretary both as attorney general and as a U.S. senator.

Guthman co-edited three books on Kennedy.

He also spent 20 years teaching at the University of Southern California and was one of the reporters on President Richard Nixon's infamous "Enemy's List," although the Times said Guthman contended there was no merit to that designation.

Guthman, a combat veteran of World War II, was featured in Tom Brokaw's best-selling book "The "Greatest Generation."