The prosecutor in a criminal case shall:
Tex. Disc. R. Prof. Cond. 3.09
Comment:
Source and Scope of Obligations
1. A prosecutor has the responsibility to see that justice is done, and not simply to be an advocate. This responsibility carries with it a number of specific obligations. Among these is to see that no person is threatened with or subjected to the rigors of a criminal prosecution without good cause. See paragraph (a). In addition a prosecutor should not initiate or exploit any violation of a suspect's right to counsel, nor should he initiate or encourage efforts to obtain waivers of important pre-trial, trial, or post-trial rights from unrepresented persons. See paragraphs (b) and (c). In addition, a prosecutor is obliged to see that the defendant is accorded procedural justice, that the defendant's guilt is decided upon the basis of sufficient evidence, and that any sentence imposed is based on all unprivileged information known to the prosecutor. See paragraph (d). Finally, a prosecutor is obliged by this rule to take reasonable measures to see that persons employed or controlled by him refrain from making extrajudicial statements that are prejudicial to the accused. See paragraph (e) and Rule 3.07. See also Rule 3.03(a)(3), governing ex parte proceedings, among which grand jury proceedings are included. Applicable law may require other measures by the prosecutor and knowing disregard of those obligations or a systematic abuse of prosecutorial discretion could constitute a violation of Rule 8.04.
2. Paragraph (a) does not apply to situations where the prosecutor is using a grand jury to determine whether any crime has been committed, nor does it prevent a prosecutor from presenting a matter to a grand jury even though he has some doubt as to what charge, if any, the grand jury may decide is appropriate, as long as he believes that the grand jury could reasonably conclude that some charge is proper. A prosecutor's obligations under that paragraph are satisfied by the return of a true bill by a grand jury, unless the prosecutor believes that material inculpatory information presented to the grand jury was false.
3. Paragraph (b) does not forbid the lawful questioning of any person who has knowingly, intelligently and voluntarily waived the rights to counsel and to silence, nor does it forbid such questioning of any unrepresented person who has not stated that he wishes to retain a lawyer and who is not entitled to appointed counsel. See also Rule 4.03.
4. Paragraph (c) does not apply to any person who has knowingly, intelligently and voluntarily waived the rights referred to therein in open court, nor does it apply to any person appearing pro se with the approval of the tribunal. Finally, that paragraph does not forbid a prosecutor from advising an unrepresented accused who has not stated he wishes to retain a lawyer and who is not entitled to appointed counsel and who has indicated in open court that he wishes to plead guilty to charges against him of his pre-trial, trial and post-trial rights, provided that the advice given is accurate; that it is undertaken with the knowledge and approval of the court; and that such a practice is not otherwise prohibited by law or applicable rules of practice or procedure.
5. The exception in paragraph (d) recognizes that a prosecutor may seek an appropriate protective order from the tribunal if disclosure of information to the defense could result in substantial harm to an individual or to the public interest.
6. Sub-paragraph (e) does not subject a prosecutor to discipline for failing to take measures to prevent investigators, law enforcement personnel or other persons assisting or associated with the prosecutor, but not in his employ or under his control, from making extrajudicial statements that the prosecutor would be prohibited from making under Rule 3.07. To the extent feasible, however, the prosecutor should make reasonable efforts to discourage such persons from making statements of that kind.
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