William Johnson, 78, who was involved in public life in New Hampshire for 40 years, 14 of them as a state Supreme Court justice, collapsed and died May 30 while walking to a hotel room in Roanoke Rapids, N.C., his family said.

He was planning to attend his granddaughter's high school graduation, the New Hampshire Union Leader reported.

Judge Johnson spent four years in the state legislature in the 1960s. He was chairman of the state Republican Party, ran for the U.S. Senate in 1966, and played key roles in the New Hampshire presidential campaigns of George Romney and Nelson Rockefeller.

Named a superior court judge in 1969, he joined the state Supreme Court in 1985 and retired in 1999.

- AP