CONCURRING OPINION OF
KIDWELL, J.I concur in the result reached by the court in these cases. However, in announcing that indictments may be attacked for failure of the prosecutor to present to the grand jury evidence which is “clearly exculpatory” the opinion fails to provide adequate guidance and proposes a standard which is open to varying interpretation. The rationale of the opinion dictates a more restrictively defined standard. I add these remarks to indicate what I believe to be the criteria which should govern.
The opinion confirms that a grand jury proceeding is not adversary in nature. An application of this principle is found in the rule that an indictment may not be attacked on the ground of the incompetency of the evidence considered by the grand jury, where prosecutorial misconduct is not involved. State v. Layton, 53 Haw. 513, 497 P.2d 559 (1972); United States v. Calandra, 414 U.S. 338 (1974). The function of a *257grand jury to protect against unwarranted prosecution does not entail a duty to weigh the prosecution’s case against that of the defense, or even to determine that the prosecution’s case is supported by competent evidence.
On the other hand, an indictment that is the result of prosecutorial misconduct or other circumstances which prevent the exercise of fairness and impartiality by the grand jury may be successfully attacked. State v. Joao, 53 Haw. 226, 491 P.2d 1089 (1971); State v. Pacific Concrete and Rock Co., 57 Haw. 574, 560 P.2d 1309 (1977). I view the opinion as equating the withholding of clearly exculpatory evidence with prosecutorial misconduct in the context of these decisions. The criteria by which clearly exculpatory evidence is to be identified should accordingly be determined with reference to the prosecutor’s function.
The conclusions reached in the cases here before the coúrt make it clear that the prosecutor’s function does not include the presentation of the potential defense to the grand jury. While not precluded from presenting conflicting evidence to the grand jury, the prosecutor need ordinarily present only the evidence which supports the prosecution’s case. At least where the prosecutor may in good faith choose to rely upon a version of the facts supported by evidence, the decisions in these cases demonstrate that he need not also present to the grand jury another version which tends to negate guilt.
The opinion suggests, as examples of situations in which clearly exculpatory evidence is required to be presented to the grand jury, instances in which evidence which is not directly contradicted places the accused away from the scene of the crime or shows that a witness has perjured himself. Each of the examples presents a situation in which the withholding of the evidence may be viewed as deliberately misleading the grand jury. Since the evidence in question is uncontradicted, the hypothetical case is necessarily one in which guilt depends on circumstantial evidence. I see as the unstated premise of the examples the proposition that a prosecutor may not, in his presentment to the grand jury, build a circumstantial case upon only a part of the circumstances which the prosecution must acknowledge to be existing, and *258is under a duty at least to acquaint the grand jury with all of the relevant circumstances which he expects the evidence to show if all conflicts are resolved in favor of the prosecution. I agree with this proposition, but question whether this court can so clearly foresee all possible circumstances that an unvarying rule can be stated to govern cases of the sort dealt with in the examples. Where the prosecutor can in good faith assert that the exculpatory evidence is contradicted by circumstantial evidence of guilt, I would not treat the case as different in principle from one in which the exculpatory evidence is directly contradicted by an eye witness.
I conclude that evidence should be considered clearly exculpatory within the meaning of the opinion only when the prosecution could not in good faith rely on other evidence. My approach is consistent with what I believe to be the underlying assumptions in the opinion of the court. While I am unable to join in the opinion, my concern is with respect to expressions which are extraneous to the decision of the cases before the court. The precise application in other cases of the principle for which I believe that the opinion stands is a matter for future determination.