He therefore concludes that violation of a statute designed to afford protection to an accused is sufficiently grievous to constitute "substantial injustice." In support of his argument that substantial injustice is inherent in a violation of section 112-6(a), the defendant distinguishes People v. Toolen (1983), 116 Ill. App.3d 632, People v. Jackson (1978), 64 Ill. App.3d 307, and People v. Hunter (1978), 61 Ill. App.3d 588, which hold that undue influence or coercion will not be presumed from the authorized presence in the grand jury room of someone other than the State's Attorney and his or her reporter. The defendant notes that the victim's mother in this case, unlike the persons involved in Toolen, Jackson, and Hunter, was not authorized to attend the session of the grand jury.

• 5 "[A] grand jury is not restricted to considering only evidence of a particular offense alleged to have been committed by an accused and often considers other possible charges." ( People v. Jackson (1978), 64 Ill. App.3d 307, 310-11, 381 N.E.2d 316, 319.) Moreover, even if some improper evidence may have been presented to the grand jury, that fact does not invalidate an indictment as long as competent witnesses have testified before the grand jury.

¶ 39 A defendant seeking to have a grand jury's indictment dismissed on grounds of prosecutorial misconduct faces a formidable task. People v. Jackson, 64 Ill.App.3d 307, 310 (1978). This court has previously noted the rarity in which Illinois courts will dismiss a grand jury's indictment on this basis.

In the sense of a grand jury proceeding, "prejudicial effect" means the defendant would not have been indicted but for the misconduct. Hall, supra; People v. Jackson, 64 Ill.App.3d 307, 21 Ill.Dec. 238, 381 N.E.2d 316 (1978). To determine whether misconduct gives rise to a dismissal, a reviewing court will have to balance the gravity and the seriousness of this misconduct with the sufficiency of the evidence supporting the probable cause finding.

"[E]ven if improper evidence had been presented to the grand jury, Illinois cases would traditionally uphold the propriety of the indictment as long as, as here, competent witnesses testified before the grand jury." People v. Jackson, 64 Ill. App. 3d 307, 312, 381 N.E.2d 316, 320 (1978). Therefore, defendant suffered no prejudice from counsel's failure to investigate or raise the alleged grand jury manipulation on appeal.

However, prejudice must be established to demonstrate error requiring dismissal of a grand jury proceeding. ( People v. Jackson (1978), 64 Ill. App.3d 307, 381 N.E.2d 316.) An indictment need not be dismissed when no intentional false or misleading evidence was presented to the grand jury. People v.Kline (1981), 99 Ill. App.3d 540, 425 N.E.2d 562.

( People v. Hunter (1978), 61 Ill. App.3d 588, 376 N.E.2d 1065.) It is not apparent from the court's opinion whether the two officers had also been witnesses before the grand jury, because even though the court referred to the presence of the officers during the testimony "of other witnesses," the proceedings at the grand jury were not examined in detail in the opinion. In People v. Jackson (1978), 64 Ill. App.3d 307, 381 N.E.2d 316, it was determined that the presence of an investigator who asked questions of a grand jury witness was concededly erroneous, but did not prejudice the defendant. The authorities interpreting section 112-6(a) thus do not define the permissible limits of the presence of other parties in the grand jury room.

( People v. Lawson (1977), 67 Ill.2d 449, 455, 367 N.E.2d 1244, 1246; People v. Leannah (1979), 72 Ill. App.3d 504, 391 N.E.2d 187.) That power also extends to the conduct of the prosecutor before a grand jury. ( People ex rel. Sears v. Romiti (1971), 50 Ill.2d 51, 277 N.E.2d 705; People v. Massarella (1978), 72 Ill.2d 531, 539, 382 N.E.2d 262, 266; People v. Jackson (1978), 64 Ill. App.3d 307, 310, 381 N.E.2d 316, 318; see also People v. Linzy (1978), 62 Ill. App.3d 97, 379 N.E.2d 58; People v. Buffalo Confectionery Co. (1978), 67 Ill. App.3d 112, 385 N.E.2d 407; Hughes v. Kiley (1977), 67 Ill.2d 261, 267, 367 N.E.2d 700, 702.) It is well established that the burden is on the defendant in these circumstances also to show that the prosecutorial conduct complained of resulted in actual and substantial prejudice to him ( Lawson, 67 Ill.2d 449, 459, 367 N.E.2d 1244, 1248) and, as we noted earlier, defendant has failed to do so in this case. We conclude that failure of the State's Attorney to advise the grand jury of its right to subpoena defendant, if it occurred, would not under these circumstances authorize the trial court to dismiss the indictment against him.