Opinion
BARROW, J.This is a criminal appeal of convictions of first degree murder, robbery and two charges of the use of a firearm in connection with the murder and the robbery. The principal issue is whether the trial judge erred in failing to require the prosecution to produce a confederate’s confession that he, rather than the defendant, actually shot the victim. We hold that the trial court’s failure to require disclosure of the confession violated the defendant’s due process right to access to all exculpatory evidence in the Commonwealth’s possession. We also conclude that it is not necessary to address the remaining two issues because one was not properly preserved and because the other is not likely to reoccur if there is a new trial.
The victim was found shot to death at his home. He was a drug dealer who had sold drugs to other drug dealers, including the defendant, and had become an informant for the police. Various jewelry which he had been wearing on the previous evening was missing. Two pieces of the jewelry, a diamond ring and a gold *101bracelet, were pawned by the defendant the morning after the victim’s body was discovered. At the same time, the defendant showed the pawn broker an unusual Rolex watch, similar to one worn by the victim, but then decided not to pawn it. After his arrest, the defendant told an inmate in the Henrico County jail that he had received $15,000 for killing the victim from other drug dealers who were afraid the victim would testify against them.
Prior to trial, the prosecutor told defense counsel that he had a confession in which a confederate admitted he actually shot the victim but that the defendant was present and that “they did the killing together.” Defense counsel filed a motion for discovery which sought, among other things, exculpatory material. In response, the trial court ordered the Commonwealth’s attorney to provide the defendant with any exculpatory evidence, but expressly excluded the confederate’s confession from that order. The trial court did not examine the confession; therefore, a copy of it was not made a part of the record.
“[Suppression by the prosecution of evidence favorable to an accused upon request violates due process where the evidence is material either to guilt or to punishment. . . .” Brady v. Maryland, 373 U.S. 83, 87 (1963). Thus, if the confederate’s confession was exculpatory, it should have been made available to the defendant.
A confederate’s admission that he or she actually killed the victim favors an accused in a murder trial. Id. It may favor an accused on the question of guilt or innocence because it tends to show that someone else, not the accused, committed the crime. Furthermore, even if the confederate’s confession implicates the accused as a principal in the second degree, as it did in this case, it may favor the accused on the issue of punishment. Cf. Poole v. Commonwealth, 211 Va. 262, 267, 176 S.E.2d 917, 920 (1970).
The confederate’s confession in this case favored the defendant on the issue of his guilt or innocence. Evidence that someone else actually had shot the victim would have directly rebutted the prosecution’s contention that the defendant had done so. If evidence of that fact also placed the defendant at the scene, this would not have been sufficient in itself to establish any criminal responsibility of the defendant. Augustine v. Commonwealth, 226 *102Va. 120, 124, 306 S.E.2d 886, 888 (1983). Even if the confederate’s confession included evidence that the defendant and his confederate “did the killing together,” as described by the prosecutor, the jury would have had to believe that portion of the confederate’s confession in order to find the defendant a principal in the second degree.
The confederate’s confession contradicted the prosecution’s theory of the case. All of the evidence presented at trial by the prosecution pointed to the defendant as the actual murderer; there was no evidence that anyone else was present. The confederate’s confession suggested two contrary theories, both of which were favorable to the defendant depending on how much of the confederate’s confession the jury found credible: that the defendant was present, aiding and abetting or that he was merely present.
Furthermore, the confederate’s confession was favorable to the defendant on the issue of punishment. Evidence that would have permitted the jury to conclude that the defendant was a principal in the second degree instead of the actual murderer was a circumstance in mitigation of the sentence imposed.
The Commonwealth argues that the prosecution did disclose the exculpatory portions of the confederate’s confession and that the defendant cannot contend otherwise because there was no proffer of any other parts of the confession. We disagree. The brief description of the confession by the prosecutor was conclusory and did not satisfy the obligation to produce the exculpatory material; however, it was sufficient to permit a determination of its exculpa- ■ tory nature. The Commonwealth’s position is untenable as it would require the defendant to have access to the very confession, the production of which the defendant seeks, in order to pursue an appeal.
Even though the confession is exculpatory, it also must be material in order to justify a new trial. In determining materiality, the standard of materiality applicable to post-conviction attacks is applicable even though this is a direct appeal. Correll v. Commonwealth, 232 Va. 454, 465, 352 S.E.2d 352, 358, cert. denied, 482 U.S. 931 (1987); Robinson v. Commonwealth, 231 Va. 142, 151, 341 S.E.2d 159, 164 (1986); but see Robinson, 231 Va. at 158-59, 341 S.E.2d at 169 (Compton, J., dissenting); People v. Morris, 46 Cal. 3d 1, 30 n.14, 756 P.2d 843, 861 n.14, 249 Cal. Rptr. 119, *103137 n.14 (1988). Under this standard, the evidence is material “only if there is a reasonable probability that, had the evidence been disclosed to the defense, the result of the proceeding would have been different.” United States v. Bagley, 473 U.S. 667, 682 (1985).
The potential significance of the withheld confession is indicated by a question from the jury during its deliberations. The jury inquired:
Please clarify. If accused was present at time of murder but did not actually pull the trigger, can he be convicted of first degree murder?
While discussing the jury’s question, the prosecutor told the trial court: “I’m not real sure where they got the idea that somebody else was involved.” The jury never knew what may have been the true story because the prosecution was permitted to withhold from the defense evidence that was inconsistent with its own theory.
By allowing the prosecution to withhold evidence that may have tended either to exculpate the defendant or reduce his punishment, the trial court helped to “shape a trial that. . . [bore] heavily on the defendant.” Brady, 373 U.S. at 87-88. It cast “the prosecutor in the role of an architect of a proceeding that [did] not comport with standards of justice.” Id. at 88.
Even if the confederate’s confession was inadmissible, it may have affected the defendant’s trial preparation. A factor in determining the materiality of undisclosed information is “[a]ny adverse effect that the prosecutor’s failure to respond might have had on the preparation and presentation of the defendant’s case.” Bagley, 473 U.S. at 683.
An extrajudicial statement may be vitally important in the preparation and conduct of a criminal trial. It may identify witnesses and other resources for further investigation. It may be used to refresh a witness’ recollection. Harrison v. Middleton, 52 Va. (11 Gratt.) 527, 545 (1854). It may be used under certain circumstances as evidence of a past recollection recorded. Farmer v. Commonwealth, 205 Va. 609, 610, 139 S.E.2d 40, 42 (1964); C. Friend, The Law of Evidence in Virginia § 18 (3d ed. 1988).
*104Such a statement may also be used as a basis for cross-examining witnesses. In this case, defense counsel’s attempt to cross-examine the police officer in charge of the investigation concerning the existence of the confederate’s confession was thwarted when the Commonwealth objected. The trial court allowed the question with the condition that the Commonwealth would have “then every right to show the extent of that statement . . . that somebody else pulled the trigger but that your man was there.”
With only the Commonwealth attorney’s limited disclosure of the content of the confession, defense counsel did not know “the extent” of the confession, the precise manner in which the confession placed White at the crime scene, or even the accuracy of the prosecutor’s characterization. Denying defense counsel the opportunity to learn the full content of the confession placed him in the position of having to rely solely upon the Commonwealth’s summary of the confession while attempting to cross-examine the investigating officer. Faced with a dilemma in which the unknown could prove more damning than the known, defense counsel withdrew his inquiry, stating, “Well, if your Honor please, I don’t know at this point what the statement says other than what the Commonwealth has recited it says.” Without knowing whether the confession merely confirmed White’s presence or culpably implicated him in the crime, defense counsel was deprived of any meaningful opportunity to cross-examine the officer concerning the confession.
In addition, the possibility that any adverse effect on preparation and presentation of the defendant’s case might have occurred must be assessed “in light of the totality of the circumstances and with an awareness of the difficulty of reconstructing in a post-trial proceeding the course that the defense and the trial would have taken had the defense not been mislead by the prosecutor’s incomplete response.” Bagley, 473 U.S. at 683. In this case, we do not know with certainty what course the defense or the trial would have taken had the defense been given the confederate’s confession.
It is possible that, even if the defense had obtained the confession, it would have chosen to pursue the same defense that it did at trial, emphasizing the weakness of the circumstantial evidence and the unreliability of the purported confession to a fellow inmate. It is likely, however, that, armed with the confession, the *105defense would have been able to elicit evidence of the confederate’s involvement either through its own witnesses or through cross-examination of the prosecution’s witnesses.
Our ability to judge the materiality of the confession is limited, however, by the absence of the full confession. If the Commonwealth’s disclosure in fact revealed the entire content of the confession, no further disclosure could be required and we would conclude that the confession was material. The confession, if believed, would have mitigated the defendant’s culpability since it would have revealed that someone else shot the victim. It is reasonably probable that disclosure of this confession would have produced a different result, at least on the issue of punishment. Defense counsel, not knowing the complete content of the confession, was forced to elicit it at trial only at an untenable risk.
If, however, the disclosure was not complete, as the Commonwealth’s attorney’s refusal to disclose would suggest, the undisclosed portion of the confession may have so inculpated the defendant in the crime that its disclosure would not have mitigated his culpability. This court is placed in the same position as defense counsel when he attempted to cross-examine the police officer about the confession: without knowing its full content, we are unable to measure the full extent of its materiality. Although we know that it was exculpatory, at least in part, we cannot say without qualification whether it was material or not. The materiality of the confederate’s confession can only be determined from an evaluation of the entire document in light of all the circumstances.
We conclude, therefore, that the confederate’s confession was exculpatory and should have been disclosed to the defendant. Consequently, we must remand this proceeding to the trial court for it to order the Commonwealth to disclose the confession so that the court may determine whether parts of the confession were not initially disclosed and, if so, whether the undisclosed parts of the confession bear upon the question of the materiality of the confession.
The remaining issues raised by the defendant need not be addressed. The first, the admissibility of the defendant’s statement to a pawnbroker that his father had been shot by the FBI, was not objected to in a timely manner. No objection was made at the time of the question or the answer, and the issue was not raised *106until after extensive direct examination and cross-examination had followed the introduction of the evidence. It was then offered as the basis for a motion for a mistrial. Had the objection been promptly made, the trial court could have corrected any error with a prompt instruction to the jury. Since this objection came too late and since no good causé has been shown nor any reason for this court to consider this issue to meet the ends of justice, this issue may not now be the basis for reversal. See Rule 5A:18; Ingram v. Commonwealth, 1 Va. App. 335, 341, 338 S.E.2d 657, 660 (1986).
The defendant’s final issue also need not be addressed. He contends that evidence that the defendant’s mother had refused to talk to the prosecutor was inadmissible. When this testimony was elicited by the prosecution, the trial court immediately directed the jury to disregard the question and the answer. See Saunders v. Commonwealth, 218 Va. 294, 303, 237 S.E.2d 150, 156 (1977). Since this issue is not likely to reoccur upon retrial, it is not necessary that we address it further.
For these reasons, we vacate the defendant’s convictions and remand the proceeding for the trial court to determine the materiality of the confederate’s confession. If it is material, the defendant shall be granted a new trial. If not, the trial court shall reinstate the convictions.
Vacated and remanded.
Benton, J., concurred.