 His father's kidnapping on 15 April 1977 prompted Timerman to become active in the defense of human rights, however, and in 1978 he was exiled to New York City, where, in 1981, he co-founded Americas Watch, the Western Hemisphere counterpart to Helsinki Watch that proceeded the creation of the unified Human Rights Watch.He later served in the board of directors of the Fund for Free Expression, a press freedom advocacy group based in London.During his exile in the U.S, he gained American citizenship.