HINES, J.

Leslie W. O'Brien for the defendant.

Robert C. Thompson, Assistant District Attorney, for the Commonwealth.

Anthony C. Biagioli, of the District of Columbia, & Kirsten V. Mayer & Chauncey B. Wood, Boston, for Massachusetts Association of Criminal Defense Lawyers, amicus curiae, submitted a brief.

Present: GANTS, C.J., SPINA, CORDY, BOTSFORD, DUFFLY, LENK, & HINES, JJ.

Opinion

HINES, J.

Based on a shooting that occurred after a party ended in Brockton in 2007, a jury, in March, 2014, convicted the defendant

of murder in the second degree, unlawful possession of a firearm, unlawful possession of a loaded firearm, and unlawful possession of ammunition. Represented by new counsel on appeal, the defendant argues (1) that the denial of immunity to two defense witnesses violated his right to a fair trial and due process of law, as well as his right to present a complete defense; and (2) error in the prosecutor's closing argument. We affirm the defendant's convictions.

Background. We recite the facts the jury could have found based on the Commonwealth's case, see Commonwealth v. Latimore, 378 Mass. 671, 676–677, 393 N.E.2d 370 (1979), reserving certain details for our discussion of the specific issues raised. The victim, Jose Gurley, who was seventeen years of age, was shot sometime around 3 a.m. on July 21, 2007, on a street outside a vacant home in Brockton where he had just attended a party. He did not appear to be the intended victim of the shooting. Rather, when gunshots erupted, the victim was speaking with one of the young men, Tyson Muzzy, with whom he had gone to the party. The victim, Muzzy, Dina Willis, Markeen Starks, and Jamar Martin earlier had traveled to the party together from Martin's home. Before that, the victim had visited with his good friend Kashin Nembhard and David Stewart.

Over fifty youths attended the party. A friend of the victim's, Elijah Finch, went to the party with Ronald Woods. There, Finch danced with his former girl friend, Sanovia Chabis, who had gone to the party with her sister. Chabis also danced with Matthew Engram, who had come to the party with his friend Ernst Verdieu.

After the party ended, many youths congregated on the adjacent street. While Chabis was speaking with Engram, Finch interrupted and an argument between the men ensued. Finch was upset that Chabis was speaking with Engram. Chabis decided to leave with her sister and headed to the vehicle in which they had arrived. Engram went to the trunk of his automobile. He testified that he opened his trunk to intimidate Finch, but he intended only

to change his sneakers. After he changed his shoes, Engram closed the trunk and stepped onto the sidewalk.

Concerning what next took place, there were different accounts. Shots were heard, but the number of shots heard varied among the witnesses. Chabis's sister heard five or six gunshots. Chabis heard four gunshots. Muzzy recalled seven. No one stated who the shooter was.

The police charged Engram with being an accessory after the fact, suspecting him of helping the shooter escape by driving him away. The charges later were nol prossed.

During their investigation, police learned from a witness, Iesha Strickland, that the shots had come from Finch's direction. Strickland reported that, after the victim's death, Finch threatened her, struck her friends, and fired a gun at her home. In response to these allegations and investigation concerning them, police commenced charges against Finch, but later dismissed them.

At trial, Engram testified that the defendant was the shooter and that the following occurred. Just before the shooting, the defendant approached Engram and put a gun to his hip and ribs, and told Engram to leave his “homey” alone. The defendant checked to see whether Engram was armed, and then the two men agreed that they were “good.” Engram turned to walk away and heard “pops.” He saw the defendant shoot the victim. Engram fled in his automobile. Verdieu went with him, and they gave a bystander named “Berbi” a ride. During cross-examination, Engram acknowledged that in October, 2012, he told defense counsel that Nembhard had not been present at the scene of the shooting.

Nembhard testified to the following. After the party, Finch had an argument with a man named “Poka” (Nembhard did not know Poka's real name). It was a “hood beef,” meaning an argument with another gang. Poka was in the same gang as Engram, Verdieu and a person named “Grey.” During the argument between Finch and Poka, the victim yelled, “Ffrruupp,” which, Nembhard later

told police, is an invitation to fight. Engram was not involved. The defendant was standing near Engram. Before the shooting, Poka said something to the defendant. After Poka made a statement to the defendant, the defendant walked through the crowd, pulled out a gun, and fired. People ran away. The defendant was wearing a black hat and T-shirt.

Woods, who had known the victim since junior high school, testified that after the party he was standing outside talking to the victim when the victim was shot. Before the shooting, Finch had been arguing with the person who was the disc jockey at the party. Another man, who was wearing a black shirt, shorts, and shoes, was the shooter. The shooter came from behind and said nothing to the victim or to him. At trial, Woods made an in-court identification of the defendant as the shooter. Earlier, after Nembhard had spoken with police, they contacted Woods, who, in November, 2010, selected the defendant's photograph from an array and identified him as the shooter. Woods testified that the shooter fled the scene in a white van and that he (Woods) tried to comfort the victim by holding him.

The defendant did not testify. Defense counsel argued that either Engram or Finch had killed the victim while shooting at each other. Defense counsel attacked the credibility of Engram, Nembhard, and Woods.

Discussion. 1. Denial of immunity to defense witnesses. The defendant contends that his State and Federal constitutional rights to a fair trial and due process, as well as his right to present a complete defense, were abridged when the trial judge declined to grant immunity to two potential defense witnesses: Verdieu and Stewart. After the Commonwealth had rested, defense counsel indicated his intent to call these two witnesses at trial, but through counsel, each asserted the privilege against self-incrimination

under the Fifth Amendment to the United States Constitution. After conducting in camera hearings pursuant to Commonwealth v. Martin, 423 Mass. 496, 504, 668 N.E.2d 825 (1996), from which no sealed hearing transcripts were provided to us, see Pixley v. Commonwealth, 453 Mass. 827, 835, 906 N.E.2d 320 (2009), the judge determined that each potential witness had a valid privilege and could not be compelled to testify. Defense counsel objected, stating that the prosecutor's selective grant of immunity deprived him from presenting exculpatory evidence from these two witnesses. Defense counsel provided an offer of proof. He first explained that he had expected Verdieu to testify, contrary to Engram's testimony, that before the shooting, the defendant had not placed a gun to Engram's body and had not stated to Engram to leave his “homey” alone. Defense counsel further expected Verdieu to testify that he never saw the defendant with a gun and had not seen the defendant shoot the victim. Concerning Stewart, defense counsel expected him to testify that Nembhard never went to the party and had stayed with him instead of attending the party.

Recently, in Commonwealth v. Vacher, 469 Mass. 425, 437, 439–441, 14 N.E.3d 264 (2014), we rejected constitutional challenges to the witness immunity statute, G.L. c. 233, §§ 20C –20E, that were based on the fact that, as relevant here, an order granting immunity to a trial witness may be issued only “at the request of the attorney general or a district attorney,” id. at 437, 14 N.E.3d 264, quoting G.L. c. 233, § 20E (a ). We explained:

“Our jurisprudence has not vested criminal defendants with expansive rights vis-à-vis the immunization of witnesses. To the contrary, ‘[w]e have held, without qualification, that a defendant “has no standing to argue that the testimony of ... purportedly immunized witnesses [is] the product of improper grants of immunity,” ’ reasoning that ‘[t]he privilege against self-incrimination is a personal right of the witness, and one that the witness is in a position to protect by his own means.’ Smith v. Commonwealth, 386 Mass. 345, 349 (1982), citing Commonwealth v. Simpson, 370 Mass. 119, 121 (1976). While a prospective defense witness's assertion of his right under the Fifth Amendment ... could affect a defendant's ability to present his defense most effectively, the compulsory process provisions of the Federal and State Constitutions do not mandate a judicial grant of immunity to such a witness as a matter of course. See Commonwealth v. Curtis, 388 Mass. 637, 646 (1983), S. C., 417 Mass. 619 (1994). Although we have left open the possibility that ‘unique circumstances' could require a judge to grant a limited form of immunity to a defense witness, see id., we have not been presented yet with such a scenario. See [Pixley, 453 Mass. at 834 n. 7, 906 N.E.2d 320 ].”

Vacher, supra at 438–439, 14 N.E.3d 264. We noted that “[o]ther courts have recognized that such unique circumstances might emerge ‘where there exists prosecutorial misconduct arising from the government's deliberate intent to distort the fact-finding process” (quotation and citation omitted). Id. at 439, 14 N.E.3d 264, and cases cited. As correctly noted by the defendant, most Federal courts have taken this same position and, absent a showing of prosecutorial misconduct, decline to grant immunity to a defense witness. See Commonwealth v. Doherty, 394 Mass. 341, 344 n. 4, 476 N.E.2d 169 (1985), and cases cited. See also United States v. Mackey, 117 F.3d 24, 27 (1st Cir.), cert. denied, 522 U.S. 975, 118 S.Ct. 431, 139 L.Ed.2d 331 (1997) (stating majority rule that Federal courts lack power to compel witness immunity in face of good faith refusal by prosecutor), and cases cited.

The defendant argues that prosecutorial misconduct need not be the sole predicate for a judicial grant of immunity. In support

of his argument, he cites to Government of the Virgin Islands v. Smith, 615 F.2d 964, 969–974 (3d Cir.1980). This case, however, has been overturned and thus offers no support for the defendant's position. See United States v. Quinn, 728 F.3d 243, 252–253 (3d Cir.2013), cert. denied, ––– U.S. ––––, 134 S.Ct. 1872, 188 L.Ed.2d 916 (2014) (concluding that in absence of prosecutorial misconduct, courts lack authority to grant use immunity to defense witness and expressly overturning Smith, supra, decision, noting that immunity is statutory creation within exclusive realm of prosecution).

In addition, the defendant cites to United States v. Straub, 538 F.3d 1147, 1162 (9th Cir.2008), in which the United States Court of Appeals for the Ninth Circuit held that “for a defendant to compel use immunity the defendant must show that: (1) the defense witness's testimony was relevant; and (2) either (a) the prosecution intentionally caused the defense witness to invoke the Fifth Amendment right against self-incrimination with the purpose of distorting the fact-finding process; or (b) the prosecution granted immunity to a government witness in order to obtain that witness's testimony, but denied immunity to a defense witness whose testimony would have directly contradicted that of the government witness, with the effect of so distorting the fact-finding process that the defendant was denied his due process right to a fundamentally fair trial.” In applying its conclusion, the court noted that the denial of immunity to the defense witness had the effect of distorting the fact-finding process because the testimony from the one immunized witness was the sole evidence establishing the elements of the crime. Id. at 1163. In this case, we cannot say the same. Although Engram testified pursuant to a grant of immunity and Nembhard testified pursuant to an agreement with the United States Attorney, there also was testimony from Woods that the defendant was the shooter. Thus, denial of immunity to Verdieu and to Stewart to contradict some of the testimony of Engram and Nembhard did not leave a prosecution that depended only on evidence from an immunized witness and a witness arguably seeking to curry favor with the prosecution.

On the facts of this case, a judicial grant of immunity to Verdieu and to Stewart was not required under constitutional principles and, as in Vacher, we find no basis to depart from our established law on this subject. In addition, we find no “unique circumstances”

requiring a grant of judicial immunity to Verdieu and to Stewart. The following observations inform our decision.

As an initial matter, there has been no showing or argument that the prosecutor's discretion to grant immunity only to Engram was improperly motivated. In addition, concerning Verdieu's expected testimony, it was relevant, no doubt, to Engram's credibility insofar as it contradicted certain details of what occurred before the victim was shot. Its exculpatory nature, however, was unclear. Although Verdieu was expected to say that he did not see the defendant with a gun and did not see the defendant shoot the victim, these statements do not require a conclusion that the defendant did not shoot the victim. See Commonwealth v. Smith, 456 Mass. 476, 482, 924 N.E.2d 270 (2010) (fact that witness did not see defendant in area of shooting does not mean that defendant did not shoot victim). It could have been that Verdieu was not looking at the defendant when shots were fired. Further, the proffer concerning Verdieu's testimony did not indicate whether Verdieu even saw who shot the victim. Again, he may have not seen the shooting at all. The proffer was neither complete nor clear. We have stated that “if the proffered testimony is found to be ambiguous, not clearly exculpatory, cumulative or ... relate[s] only to the credibility of the government's witnesses,” then judicial immunity is not available. See Commonwealth v. Drew, 447 Mass. 635, 645, 856 N.E.2d 808 (2006), cert. denied, 550 U.S. 943, 127 S.Ct. 2269, 167 L.Ed.2d 1106 (2007), quoting Commonwealth v. Doherty, 394 Mass. 341, 345, 476 N.E.2d 169 (1985). These principles apply here.

These principles also apply in a slightly different way to Stewart's proffered testimony. Stewart's expected testimony, that Nembhard never went to the party, was cumulative of Engram's testimony concerning his statements to defense counsel made in October, 2012. In addition, Nembhard was not an immunized witness and the jury were correctly instructed to examine his testimony with particular care. See note 6, supra. See

Vacher, 469 Mass. at 440–441, 14 N.E.3d 264 (judge's instructions concerning factors impacting witness credibility preserved defendant's right to fair trial in absence of compelled judicial immunity). Last, as has been stated, the prosecution did not satisfy the elements of its case based only on the testimony of an immunized witness; rather, Woods also testified that the defendant was the shooter. Defense counsel was able to thoroughly cross-examine him (as well as Engram and Nembhard), and the jury correctly were instructed that they could not convict the defendant solely on the basis of Engram's testimony. See id. at 440, 14 N.E.3d 264. On this record, the judge properly declined to order immunity to Verdieu and to Stewart outside the prescribed statutory scheme.

2. Prosecutor's closing argument. The defendant argues that the prosecutor engaged in improper vouching and misstated the evidence. Because defense counsel did not object, we review the prosecutor's closing argument to determine whether there was error, and, if so, whether it created a substantial risk of a miscarriage of justice. Commonwealth v. Smith, 460 Mass. 385, 398, 951 N.E.2d 674 (2011).

“While a prosecutor may not vouch for the truthfulness of a witness's testimony, [Ciampa, 406 Mass. at 265, 547 N.E.2d 314 ], we consistently have held that, where the credibility of a witness is an issue, counsel may ‘argue from the evidence why a witness should be believed.’ Commonwealth v. Raposa, 440 Mass. 684, 694–695, 801 N.E.2d 789 (2004).” Smith, 460 Mass. at 399, 951 N.E.2d 674. In context of the prosecutor's entire argument in this case, we conclude that the challenged isolated comment about Woods being a “standup guy” falls into this latter category.

The prosecutor's statement that the jurors had been given “no reason to doubt” Woods, did not, contrary to the defendant's contention, misstate the evidence. The statement was proper argument responsive to defense counsel's argument that Woods was not a credible witness. See Commonwealth v. Chavis, 415 Mass. 703, 713, 616 N.E.2d 423 (1993) (“prosecutor may make a fair response to an attack on the credibility of a government witness”).

Last, the judge's careful and clear instructions concerning the role of the closing arguments and how to determine the credibility of witnesses adequately offset any semblance of impropriety, were we to determine that one occurred. See

Commonwealth v. Mitchell, 428 Mass. 852, 857–858, 705 N.E.2d 263 (1999).

Conclusion. For the foregoing reasons, the defendant's convictions are affirmed.

So ordered.