A Superior Court judge dismissed with prejudice indictments which charged each of three defendants (William D. Petras, William Marrocco, and Charles Camirand) with aggravated rape and indecent assault and battery. The judge concluded that the ultimate sanction was necessary because the prosecutor, after being warned once before by another *484judge, failed to bring to the grand jury’s attention an inconsistent statement made by the victim at the probable cause hearing on the cases. The Commonwealth has appealed. We reverse the orders.
The eighteen year old victim’s (we shall call her Carol) testimony of the incident and other relevant background information can be summarized as follows. Carol had been acquainted with the defendant Camirand. Camirand invited Carol and her girlfriend (also eighteen) to go out with him on the evening of August 2, 1985. Camirand, accompanied by the defendants Petras and Marrocco, picked up the two women in a van. The back of the van was equipped with a bar, two captain’s chairs, two “beanbag” chairs, and a mattress. The group went to a lounge in Newburyport, where the men drank heavily. When the group left the lounge, the three men appeared to Carol to be intoxicated.
Camirand, the van’s driver, ignored the young women’s requests to be taken home, and he eventually drove the van down a deserted road. He took Carol’s friend outside the van to talk to her, leaving Carol alone in the back of the van with Petras and Marrocco. According to Carol, Petras and Marrocco “jumped” on the mattress on which she was sitting. Marrocco positioned himself “up towards [her chest],” while Petras was down “towards [her] legs.” Marrocco began kissing Carol and pulling off her shirt and bra. She pushed him away and pleaded with him to stop. Marrocco held her down, began to kiss her breasts, and attempted to force his penis into her mouth. While Marrocco restrained Carol, Petras unbuttoned and pulled off her jeans and underpants. Petras placed his fingers and then his tongue into Carol’s vagina. He then inserted his penis into her vagina.
The attack stopped when Carol’s girlfriend returned to the van. The group left in the van. The women were upset. Camirand drove Marrocco home and then stopped the van again. He then went into the back of the van and asked Carol to “give him some satisfaction.” The two women fled the van and ran into some nearby woods. They eventually reached the security office of a factory and called the police. Carol was *485taken to the Wilmington police station and then to the Lahey Clinic, where she was examined by a physician. While at the clinic, Carol wrote out and signed for a policewoman a description of the incident.
In her written statement for the police, Carol referred to Petras as the one who had “tried” to have sexual intercourse with her. Later in the same statement, she identified Petras as the “one who had intercourse with her.” The hospital record contained an entry that noted “? of penetration” and further stated (under the heading “clinical notes”) that “the patient thinks no vaginal penetration.”
We next summarize the procedural history of the case. Carol testified about the incident along the lines outlined above at a lengthy probable cause hearing in a District Court. She was cross-examined by counsel for each of the three defendants and was impeached with the information in her police statement and the hospital record. At this hearing, she indicated that Marrocco, while holding her down, had tried to insert his penis into her mouth but was unsuccessful, as she had “shut her mouth” and turned her head away. In cross-examination by Marrocco’s counsel, she further testified as set forth in the margin.2 At the close of the probable cause hearing the prosecutor indicated to the District Court judge that the Commonwealth was proceeding against Marrocco solely on a joint venture theory.3
*486The prosecutor secured indictments against the three men from a grand jury based on Carol’s testimony of the incident. Petras moved to dismiss the indictments against him due to the failure of the prosecutor to advise the grand jury of the information (quoted above) contained in Carol’s written statement to the police and in the hospital record. After a hearing, a Superior Court judge (not the judge whose order led to this appeal) allowed Petras’ motion and dismissed the indictments against him without prejudice. The judge reasoned, based on the decided cases as he viewed them, that the grand jury should have been apprised of the inconsistencies, which, he concluded, might have affected their decision to indict Petras.
The prosecutor decided not to appeal from the dismissal because of the time that the appeal would have taken and because reindictment had been permitted. He entered nolle prosequis on the indictments against Marrocco and Camirand and went before another grand jury with Carol to secure new indictments against all three defendants. Carol’s testimony before the second grand jury repeated her testimony at the previous proceedings, except with respect to Marrocco’s conduct. Specifically, she testified, as set forth below, that Marrocco had in fact forced his penis into her mouth.4 Despite this addition to her testimony, the prosecutor did not allude to Carol’s probable cause testimony about Marrocco’s attempt to penetrate her. See note 2, supra. However, the prosecutor did bring out the inconsistencies concerning the actions of Petras thought material by the first judge. Based on Carol’s testimony, the second grand jury voted the indictments at issue.
The three defendants next moved to dismiss the second round of indictments on the ground that the integrity of the grand *487jury had been impaired because the prosecutor (a) had not sufficiently cured the deficiencies described by the first judge and (b) had improperly withheld Carol’s testimony at the probable cause hearing that Marrocco had not violated her.5
After a hearing, a second Superior Court judge dismissed the indictments charging each defendant with aggravated rape and indecent assault and battery. The judge essentially concluded that the defendants had demonstrated that the integrity of the second grand jury had been compromised. The judge deemed the new fact pertaining to Marrocco, as testified to by Carol before the second grand jury, when left unbalanced by her inconsistent testimony at the probable cause hearing, a significant distortion caused by the prosecutor’s intentional withholding of exculpatory evidence. The judge further concluded that the failure to inform the grand jury of this inconsistency, considered with the fact that Petras’ indictments had already been dismissed once, called for dismissal with prejudice of the aggravated rape and indecent assault charges against all defendants as the only appropriate sanction.6 We do not agree with these conclusions.
A prosecutor may not withhold known exculpatory information which could undermine the credibility of an important witness in the eyes of a grand jury and, consequently, affect their decision to indict. See Commonwealth v. O’Dell, 392 Mass. 445, 446-447 (1984); Commonwealth v. Connor, 392 Mass. 838, 854 (1984); Commonwealth v. McGahee, 393 Mass. 743, 746-747 (1985); Commonwealth v. Mayfield, 398 Mass. 615, 620-622 (1986); Commonwealth v. McGowan, 400 Mass. 385, 388-389 (1987). The prosecutor here was acutely aware from the prior dismissal that the next grand jury to hear *488the cases should be alerted to possible inconsistencies in Carol’s version of the incident. He complied with the order of the first Superior Court judge to bring to the attention of the second grand jury the information pertaining to Petras contained in Carol’s statement to the police and in the hospital record.7 Having done that, the prosecutor continued to focus on Petras as the principal actor in the aggravated rape. He sought to indict Marrocco for rape as a joint venturer based on Carol’s testimony that Marrocco held her down while Petras removed her jeans and underpants and forcefully entered her vagina with his fingers, tongue, and penis.8 See note 3, supra. There is basis to argue (as the Commonwealth does) that the prosecutor might not have considered the testimony before the second grand jury truly inconsistent because it was given in the context of Carol describing Marrocco pinning her upper body down and not entering her vagina. In any event, whether Marrocco succeeded in inserting his penis into Carol’s mouth was a fact which can fairly be said was not considered crucial by the prosecutor to Marrocco’s indictment for aggravated rape on a joint venture theory.9
The record; therefore, does not justify a conclusion that the prosecutor deliberately omitted the probable cause testimony with the “purpose prepense” of obtaining indictments. Commonwealth v. Bobilin, 25 Mass. App. Ct. 410, 413 (1988). See Commonwealth v. Mayfield, 398 Mass. at 621; Commonwealth v. Seminara, 20 Mass. App. Ct. 789, 793 (1985); Commonwealth v. Childs, 20 Mass. App. Ct. 985, 987 (1985); Commonwealth v. Pond, 24 Mass. App. Ct. 546, 551-552 (1987). At the worst, the record indicates that the prosecutor may have been negligent in his failure to comprehend all the *489nuances of Carol’s testimony arguably contradictory in detail, in the context of proceedings which, unlike a trial before a petit jury, are meant to be accusatory and nonadversary. We assume that a negligent failure by a prosecutor to disclose exculpatory information to a grand jury may, in some circumstances, rise to a level that cannot be condoned. However, we do not consider any oversight here to be one that requires the ultimate sanction of dismissal with the consequent effect that stringent remedy has of infringing upon the public’s right to see persons accused of serious crimes brought to trial. See Commonwealth v. Cinelli, 389 Mass. 197, 210 (1983). To hold otherwise in this case would run counter to the grand jury’s primary role as “a body with powers of investigation and inquisition, the scope of whose inquiries is not to be limited narrowly by questions of propriety or forecasts of the probable result of the investigation, or by doubts whether any particular individual will be found properly subject to an accusation of crime.” Blair v. United States, 250 U.S. 273, 282 (1919).
This view of the case is supported by another consideration. It cannot be persuasively argued on- this record that had the added testimony been presented, the second grand jury would not have returned the indictments. Carol’s testimony before that grand jury was both in reasonable detail and, in its material aspects, consistent with her testimony at the probable cause hearing and before the first grand jury. Her descriptions of the actions of Petras and Camirand did not vary. We doubt that knowledge of her inconsistent testimony as to one aspect of Marrocco’s conduct would have so undermined her credibility in the eyes of the grand jury that they would have rejected her testimony against all the defendants and declined to return an indictment for rape or for indecent assault and battery. Cf. Commonwealth v. Champagne, 399 Mass. 80, 85 (1987).
We conclude: (a) that the evidence before the second grand jury was sufficient to warrant a finding of probable cause as to the aggravated rape and indecent assault and battery indictments against each defendant, see Commonwealth v. Pond, 24 Mass. App. Ct. at 552, and cases cited; and (b) that the defendants have not met the “heavy burden” imposed on them, *490see Commonwealth v. Shea, 401 Mass. 731, 734 (1988), of demonstrating that the prosecutor knowingly distorted that evidence or withheld exculpatory information, which, if revealed, would have influenced the grand jury not to indict.10
The orders dismissing the aggravated rape and indecent assault and battery indictments against each defendant are reversed.
So ordered.