That drawer was an unlocked one, as he had pointed out, and he submitted that there was no evidence to prove that it was the prisoner who had concealed the poison there. 
( ( ( ( ( ( That drawer ) ( ( ( was ( an ( unlocked one ) ) ) , ) ( as ( he ( had ( pointed out ) ) ) ) ) ) , ) and ) ( he ( submitted ( that ( there ( was ( no ( evidence ( to ( prove ( that ( it ( was ( ( the prisoner ) ( who ( had ( ( concealed ( the poison ) ) there ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (DT That) (NN drawer)) (VP (VBD was) (NP (DT an) (JJ unlocked) (NN one)) (, ,) (SBAR (IN as) (S (NP (PRP he)) (VP (VBD had) (VP (VBN pointed) (PRT (RP out)))))))) (, ,) (CC and) (S (NP (PRP he)) (VP (VBD submitted) (SBAR (IN that) (S (NP (EX there)) (VP (VBD was) (NP (DT no) (NN evidence) (S (VP (TO to) (VP (VB prove) (SBAR (IN that) (S (NP (PRP it)) (VP (VBD was) (NP (NP (DT the) (NN prisoner)) (SBAR (WHNP (WP who)) (S (VP (VBD had) (VP (VBN concealed) (NP (DT the) (NN poison)) (ADVP (RB there))))))))))))))))))) (. .)))
The prisoner unlocked the draw but it wasn't him that put the poison in there.
( ( ( ( ( The prisoner ) ( unlocked ( the draw ) ) ) but ) ( it ( ( was n't ) ( him ( that ( ( put ( the poison ) ) ( in there ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (DT The) (NN prisoner)) (VP (VBD unlocked) (NP (DT the) (NN draw)))) (CC but) (S (NP (PRP it)) (VP (VBD was) (RB n't) (NP (NP (PRP him)) (SBAR (WHNP (WDT that)) (S (VP (VBD put) (NP (DT the) (NN poison)) (PP (IN in) (NP (RB there))))))))) (. .)))