whitewash something
To explain a major, national scandal in soothing official terms so as to assure the public that things are under control and there is no need to panic.
Many people in the United States believe that President Kennedy's assassination was whitewashed by the Warren Commission.
whitewash
A soothing official report that attempts to tranquilize the public.
Some people believe that the Warren Commission's report on the Kennedy assassination was a whitewash.