The violence following the September 1965 coup attempt that led to Suharto taking power in Indonesia disillusioned Anderson, who wrote that it "felt like discovering that a loved one is a murderer". Therefore, while Anderson was still a graduate student at Cornell, he anonymously co-wrote the "Cornell Paper" with Ruth T. McVey that debunked the official Indonesian government accounts of the abortive coup of the 30 September Movement and the subsequent anti-Communist purges of 1965–66. The "Cornell Paper" was widely disseminated by Indonesian dissidents. One of two foreign witnesses at the show trial of Communist Party of Indonesia general secretary Sudisman in 1971, Anderson published a translated version of the latter's unsuccessful testimony. As a result of his actions, Anderson was in 1972 expelled from Indonesia and banned from reentering, a restriction that lasted until 1998 when Suharto resigned to be replaced by B.J. Habibie as president.