(a) A statement made by a participant while counsel and advice are being given, offered, or sought, in the discussions or conferences incident to an informal adjustment may not be admitted in evidence in any adjudicatory hearing or peace order proceeding or in a criminal proceeding against the participant prior to conviction.
(b) Any information secured or statement made by a participant during a preliminary or further inquiry pursuant to § 3–8A–10 of this subtitle or a study pursuant to § 3–8A–17 of this subtitle may not be admitted in evidence in any adjudicatory hearing or peace order proceeding except on the issue of respondent’s competence to participate in the proceedings and responsibility for his conduct as provided in § 3–109 of the Criminal Procedure Article where a petition alleging delinquency has been filed, or in a criminal proceeding prior to conviction.
(c) A statement made by a child, his parents, guardian or custodian at a waiver hearing is not admissible against him or them in criminal proceedings prior to conviction except when the person is charged with perjury, and the statement is relevant to that charge and is otherwise admissible.
(d) If jurisdiction is not waived, any statement made by a child, his parents, guardian, or custodian at a waiver hearing may not be admitted in evidence in any adjudicatory hearing unless a delinquent offense of perjury is alleged, and the statement is relevant to that charge and is otherwise admissible.