The OSS did not exist during WWI and neither did the CIA.
The Office of Strategic Services was established by a Presidential military order issued by President Roosevelt on 13 June 1942 during World War II.
Prior to the formation of the OSS (the counterpart of the British Secret Intelligence Service
and Special Operations Executive
), American intelligence had been conducted on an ad-hoc basis by the various departments of the executive branch, including the State
, and War
The 1947 National Security Act established the CIA, affording it "no police or law enforcement functions, either at home or abroad".