James G. Lowenstein, who as one half of a globe-trotting investigative team with Richard M. Moose wrote a series of reports for the Senate Foreign Relations Committee in the early 1970s that undermined President Richard M. Nixon’s assessment in Viet Nam, died on Jan. 3 at his home in Washington, age 95.

President Nixon had won the White House in 1968 with the promise of a “secret plan” to end the war in Vietnam — to train and equip South Vietnamese forces so that the United States could rapidly draw down its commitment there. Senator William J. Fulbright, chair of the committee, sent the two journalists to investigate. In their report, they asserted that the plans “seem to rest on far more ambiguous, confusing and contradictory evidence than pronouncements from Saigon and Washington indicate.” The war, they concluded, “appears to be not only far from won but far from over.”