Complex sentence: After leaving Congress, Barr became critical of the Bush administration, specifically for the administration's use of the USA PATRIOT Act, which he believed was unconstitutional, and worked as a privacy consultant for the American Civil Liberties Union.
Split into simpler sentences: After leaving Congress, Barr became critical of the Bush administration, specifically for the administration's use of the USA PATRIOT Act, which Barr believed to be unconstitutional. He also worked as a privacy consultant for the American Civil Liberties Union.