concurring. I agree with the majority that the state’s attorney’s remarks do not warrant reversal of the defendant’s convictions. I write separately, however, to express my dismay at the impropriety of the state’s rebuttal argument.
It is well recognized that the state’s attorney “is not only an officer of the court, like every attorney, but is also a high public officer, representing the people of the State, who seek impartial justice for the guilty as much as for the innocent. In discharging his most important duties, he deserves and receives in peculiar degree the support of the court and the respect of the citizens of the county. By reason of his office, he usually exercises great influence upon jurors. His conduct and language in the trial of cases in which human life or liberty are at stake should be forceful, but fair, because he represents the public interest, which demands no victim and asks no conviction through the aid of passion, prejudice, or resentment. If the accused be guilty, he should nonetheless be convicted only after a fair trial, conducted strictly according to the sound and well-established rules which the laws prescribe. While the privilege of counsel in addressing the jury should not be too closely narrowed or unduly hampered, it must never be used as a license to state, or to comment upon, or to suggest an inference from, facts not in evidence, or to present matters which the jury have no right to consider.” State v. Ferrone, 96 Conn. 160, 168-69, 113 A. 452 (1921).
*578The defendant in the present case claims that the prosecutorial misconduct dining the state’s closing argument to the jury was so egregious that it deprived him of his constitutional right to a fair trial under the due process clause of both the state and federal constitutions. In analyzing the defendant’s claim, the issue is whether the prosecutor’s conduct “ ‘so infected the trial with unfairness as to make the resulting conviction a denial of due process.’ ” Darden v. Wainwright, 477 U.S. 168, 181, 106 S. Ct. 2464, 91 L. Ed. 2d 144 (1986), quoting Donnelly v. DeChristoforo, 416 U.S. 637, 643, 94 S. Ct. 1868, 40 L. Ed. 2d 431 (1974); State v. Hawthorne, 176 Conn. 367, 372, 407 A.2d 1001 (1978). We do not focus alone, however, on the conduct of the prosecutor. “ ‘The fairness of the trial and not the culpability of the prosecutor is the standard for analyzing the constitutional due process claims of criminal defendants alleging prosecutorial misconduct.’ ” State v. Palmer, 196 Conn. 157, 163, 491 A.2d 1075 (1985), quoting State v. Ubaldi, 190 Conn. 559, 562, 462 A.2d 1001, cert. denied, 464 U.S. 916, 104 S. Ct. 280, 78 L. Ed. 2d 259 (1983); see Darden v. Wainwright, supra, 180-81; State v. Doehrer, 200 Conn. 642, 654, 513 A.2d 58 (1986).
“In determining whether prosecutorial misconduct was so serious as to amount to a denial of due process, this court, in conformity with courts in other jurisdictions, has focused on several factors.” State v. Williams, 204 Conn. 523, 540, 529 A.2d 653 (1987). Included among those factors are the extent to which the misconduct was invited by defense conduct or argument; State v. Falcone, 191 Conn. 12, 23, 463 A.2d 558 (1983); the severity of the misconduct; see United States v. Modica, 663 F.2d 1173, 1181 (2d Cir. 1981) [cert. denied, 456 U.S. 989, 102 S. Ct. 2269, 73 L. Ed. 2d 1284 (1982)]; the frequency of the misconduct; State v. Couture, 194 Conn. 530, 562-63, 482 A.2d 300 (1984), cert. denied, 469 U.S. 1192, 105 S. Ct. 967, 83 L. Ed. 2d 971 (1985); see State v. Doehrer, supra, 200 Conn. 654; State v. *579Palmer, supra, 196 Conn. 164; the centrality of the misconduct to the critical issues in the case; Hawthorne v. United States, 476 A.2d 164, 172 (D.C. App. 1984); the strength of the curative measures adopted; United States v. Modica, supra, 1181; Harris v. United States, 402 F.2d 656, 657 n.1 (D.C. Cir. 1968); State v. Doehrer, supra, 654; and the strength of the state’s case. See United States v. Modica, supra, 1181; State v. Couture, supra, 564; see also State v. Glenn, 194 Conn. 483, 492, 481 A.2d 741 (1984).
The parameters of the term “zealous advocacy” are also well settled. The prosecutor may not express his own opinion, directly or indirectly, as to the credibility of the witnesses. United States v. Modica, supra, 663 F.2d 1179; United States v. Drummond, 481 F.2d 62 (2d Cir. 1973); 1 A.B.A., Standards for Criminal Justice (2d Ed. 1980) c. 3, standard 3-5.8 (b), p. 3.87. Nor should a prosecutor express his opinion, directly or indirectly, as to the guilt of the defendant. Harris v. United States, supra, 402 U.S. 658; 1 A.B.A., supra, standard 3-5.8 (b), p. 3.87. Such expressions of personal opinion are a form of unsworn and unchecked testimony, and are particularly difficult for the jury to ignore because of the prosecutor’s special position. State v. Ferrone, supra, 96 Conn. 168-69. Moreover, because the jury is aware that the prosecutor has prepared and presented the case and consequently, may have access to matters not in evidence; United States v. Modica, supra, 1178-79; it is likely to infer that such matters precipitated the personal opinions. Finally, in fulfilling his duties, the prosecutor must confine the arguments to the evidence in the record. State v. Binet, 192 Conn. 618, 631, 473 A.2d 1200 (1984); State v. Ferrone, supra, 169. Statements as to facts that have not been proven amount to unsworn testimony that is not the subject of proper closing argument. 1 A.B.A., supra, standard 3-5.8 (a), p. 3.87.
Nevertheless, during closing argument the state’s attorney in this case impermissibly vouched for the *580credibility of the prosecution witness, Esmay Notice, by personally denying that he had entered into a secret agreement with her. In response to the defendant’s argument that the jury reasonably could infer that the state had struck a deal with Notice to dismiss the aiding and abetting arson murder charges against her in exchange for her testimony, the state’s attorney first referred to the claim as “[t]his big conspiracy I guess between me and Esmay Notice” and then denied the existence of a plea bargain, thereby testifying without affording the defendant the benefit of cross-examination. “[Defense counsel] wants you to believe that I made a deal with the murderers — with the murderer of Clarence Winston, Barbara Winston, Jostin Winston and Tiana Winston. He wants you to believe that I made a deal with the murderer of Clarence, Tarley and Tiana’s parents. He wants you to think that I made a deal with the murderer of Tiana and Jostin Winston. He wants you to believe that I made a deal with the murderer of those people’s parents and that woman’s children. No way. No way.” This response constituted a form of unsworn and unchecked testimony. The state’s attorney, in effect, impermissibly testified without affording the defendant the opportunity to cross-examine him regarding the absence of a plea agreement, expressed his personal opinion that Notice was a credible witness for the prosecution, and suggested to the jury that to acquit the defendant, it must first “abandon confidence in the integrity of the government.” United States v. Goff, 847 F.2d 149, 164 (5th Cir.), cert. denied, 488 U.S. 932, 109 S. Ct. 324, 102 L. Ed. 2d 341 (1988). This “implied ‘voucher’ for [Notice’s] credibility invited the jury to view its verdict as a vindication of the prosecutor’s integrity rather than as an assessment of guilt or innocence based upon the evidence presented at trial.” Floyd v. Meachum, 907 F.2d 347, 354 (2d Cir. 1990).
A few moments later, the state’s attorney referred to certain evidence that the trial court previously had ruled *581inadmissible and then in his so-called apology exacerbated the problem. The state’s attorney argued to the jury as follows: “You know, [defense counsel] said ‘well, read the transcript, read the transcript [of Notice’s guilty pleas].’ I wish you could read the transcript. But you’re not going to read what happened on August 10 when that plea was taken because [defense counsel] edited nine pages of that transcript. It was nine or eight or seven or whatever, nine pages of that transcript he wants to give you. That doesn’t have in there what I said.” Following the defendant’s objection, which the court sustained, the state’s attorney “apologized.” “The last thing I meant to do or attempted to do was say [defense counsel] did anything wrong. The point I was trying to make is that is an edited transcript. You heard when I cross-examined the court reporter regarding the contents of that transcript. The state’s case has no excerpts, no evidence left out. That’s right. There’s one hundred — [defense counsel] read you the thing. It’s one hundred something pieces of evidence in. We didn’t edit anything. We give you all the witnesses who could give you any information about this case.”
These remarks improperly referred to evidence that had been excluded by the court. See United States v. Vaglica, 720 F.2d 388, 395 (5th Cir. 1983) (improper to “suggest to the jury that inadmissible evidence exists that bears against the defendant’s case”); United States v. Narciso, 446 F. Sup. 252, 321-22 (E.D. Mich. 1977) (prosecutor’s complaint to jury that “ ‘ [t]he Government hasn’t even been allowed to present [certain] evidence’ . . . implied strongly that evidence of the defendants’ guilt existed which was not presented”); People v. Emerson, 97 Ill. 487, 497, 455 N.E.2d 41 (1983) (improper “to suggest that evidence of guilt existed which, because of defendant’s objection, cannot be brought before the jury”); 88 C.J.S. 354-55 and nn. 56-58, Trial § 181 (a) (1955) (“improper for counsel to *582argue or comment on excluded evidence, or to express regret that the court should have excluded certain evidence from the jury, or state that the excluded evidence was admissible”). Additionally, these remarks improperly criticized defense counsel for making objections that prevented admission of the redacted portions of the transcript; J. Stein, Closing Arguments (1996) § 16, p. 52 andn.2; and improperly vouched for Notice’s credibility by “indicat[ing] that information not presented to the jury supported] [her] testimony.” United States v. Roberts, 618 F.2d 530, 533 (9th Cir. 1980).
Despite the impropriety of these remarks, the defense counsel objected only once, apparently not finding the other comments sufficiently provocative or harmful. When the objection was made to the remarks on the excluded evidence, the trial court provided curative instructions, which were sufficient to obviate the harm caused by those comments. Although the other remarks deserved responses by defense counsel and the trial court; Harris v. United States, supra, 402 F.2d 657 n.1; I nonetheless agree with the majority that, in the context of the entire trial, the conduct was not so frequent or its impact so offensive to the judicial process as to require reversal of the defendant’s convictions, nor were the remarks part of a pattern of prosecutorial misconduct requiring a new trial. Contra State v. Williams, supra, 204 Conn. 539-48. The fact that the error does not rise to the level of impropriety required to reverse a criminal conviction should not serve, however, as a sign that such patently impermissible behavior is to be tolerated.