(S (S (S (BASENP (NNP Mr.) (NNP Libby)) (VP (VBD was) (VP (VBN obliged) (S (VP (TO to) (VP (VB step) (PRT (RP down)))))))) (SBAR (IN after) (S (BASENP (PRP he)) (VP (VBD was) (VP (VBN indicted) (PP (IN on) (NP (NNS charges) (SBAR (IN that) (S (BASENP (PRP he)) (VP (VBD lied) (PP (IN about) (NP (BASENP (PRPD his) (NN role)) (PP (IN in) (S (VP (VP (VP (VBG exposing) (NP (BASENP (DT the) (NN identity)) (PP (IN of) (NP (BASENP (NNP Valerie) (NNP Plame) (NNP Wilson)) (PRN (COMMA ,) (BASENP (DT a) (NNP C.I.A.) (NN operative)) (COMMA ,)))))) (PP (TO to) (BASENP (DT the) (NN journalist) (NNP Robert) (NNP Novak)))) (PP (IN in) (BASENP (NNP July) (NN 2003)))))))))))))))))) (PERIOD .))