In January 1924 he was called from command of a minesweeper off the China coast to head the "research desk" of the Code and Signal Section within the Office of Naval Communications.

He was the first to begin organizing the worldwide Naval collection and direction finding effort, so that when the United States entered World War II it already had a system of intercept stations.

He recognized the signs of war that appeared in the diplomatic traffic, and he tried to get a warning message to Pearl Harbor several days before the attack but Director of Naval Communications Admiral Noyes rebuffed him.

That paid off in the spring of 1942, when Rochefort's team, though unable to break JN-25, the main Japanese naval operational code, was able to deduce important information from it, largely through traffic analysis, in time to help win the Battle of Midway.

About 1970 he began a lengthy analysis of the 1937 flight across the Pacific on which Amelia Earhart disappeared, and after establishing the intricate radio transmission documentation he concluded "poor planning, worse execution".

A book was subsequently published: Earhart's Flight into Yesterday: The Facts Without the Fiction by Laurance F. Safford with Cameron A. Warren & Robert R. Payne (c2003, Paladwr Press, McLean VA USA) ISBN 1-888962-20-8