(concurring, with whom Ireland, J., joins). I write separately because I do not agree with that portion of Chief Justice Marshall’s opinion (with whom Justices Abrams and Greaney join) (hereinafter the three Justices) in Part III that limits the trial judge’s discretion to admit evidence of a rape complainant’s prior convictions for prostitution to impeach the complainant’s credibility.1
The use of prior convictions to impeach the credibility of a witness is expressly authorized by G. L. c. 233, § 21. See Com*627monwealth v. Fano, 400 Mass. 296, 301-302 (1987), and cases cited. The rationale for this rule is that an “earlier disregard for the law may suggest to the fact finder similar disregard for the courtroom oath.” Id. at 303, quoting Commonwealth v. Roucou-let, 22 Mass. App. Ct. 603, 608 (1986). See Commonwealth v. Drumgold, 423 Mass. 230, 249 (1996).
This court ruled for the first time in Commonwealth v. Chase, 372 Mass. 736 (1977), that a judge has discretion under G. L. c. 233, § 21, to exclude the use of prior convictions to impeach a defendant’s credibility if there is danger of prejudice.2 Id. at 750. In Commonwealth v. Maguire, 392 Mass. 466, 470 (1984), overruling Commonwealth v. West, 357 Mass. 245 (1970), the court allowed judicial review of a judge’s discretion.
Elsewhere I have stated that, because of the statutory directive permitting use of prior convictions for impeachment, only in an extreme case would I conclude that unfair prejudice required the exclusion of such evidence, especially where the judge “gives appropriate and strong limiting instructions and ensures that the prosecutor does not misuse the evidence.” Commonwealth v. Elliot, 393 Mass. 824, 835 (1985) (Lynch, J., concurring). See Commonwealth v. Reed, 397 Mass. 440, 445-446 (1986) (Lynch, J., dissenting). Furthermore, I have expressed my disagreement with the court’s suggestion that error might arise from the admission of a defendant’s prior conviction of rape in a rape trial. See Commonwealth v. Elliot, supra.
The rape-shield statute, G. L. c. 233, § 21B, does not address the use of a complainant’s prior convictions for impeachment purposes.3 Today the three Justices see within the rape-shield statute the intent to limit the discretion of the judge to admit evidence of convictions specifically permitted by G. L. c. 233, § 21. See Commonwealth v. Joyce, 382 Mass. 222 (1981). No *628specific language of the statute supports such an interpretation. Therefore, I believe the three Justices’ opinion amounts to an implied repeal of G. L. c. 233, § 21. “[T]here is a ‘very strong presumption against implied repeal’ ” in statutory construction. Commonwealth v. Hudson, 404 Mass. 282, 286 (1989), quoting Commonwealth v. Jones, 382 Mass. 387, 391 (1981). Implied repeal should never be used unless there is a conflict between two statutes dealing with the same subject matter and the older statute is “so repugnant to and inconsistent with the later enactment . . . that both cannot stand.” Commonwealth v. Hudson, supra, quoting Boston Horn. Auth. v. Labor Relations Comm’n, 398 Mass. 715, 718 (1986). Here, the exact relationship between the two statutes may not be clear, but there is no such repugnance.
In reconciling the two statutes, I would apply the rule the court developed in Commonwealth v. Joyce, supra. Joyce provided sufficient guidance for judges when weighing the admissibility of evidence of prostitution against the rape-shield statute. The court said: “In the exercise of this discretion a trial judge should consider the important policies underlying the rape-shield statute. He should exclude evidence of specific instances of a complainant’s sexual conduct in so far as that is possible without unduly infringing upon the defendant’s right to show bias.” Id. at 231. There, the court also specifically declined to “intimat[e] the proper result” when the judge exercised discretion. Id.4
The three Justices, in part III, now opine that a judge should deny admission of a complainant’s prior convictions of prostitution to impeach the complainant’s general credibility. I find such a limit on the discretion of the judge improper because it defies the legislative directive to admit such evidence. Moreover, the three Justices themselves concede that it is not clear whether § 21B was meant to modify § 21 at rape trials. Because the legislative intent is not clear, any expansion of the rape-shield *629statute is a matter of legislative prerogative. Until the Legislature acts, I think the guidance that Commonwealth v. Joyce, supra, gave to judges that they should consider the important policies behind the rape-shield statute when exercising their discretion is equally appropriate guidance for evidence impeaching a complainant’s general credibility.
Under the rape-shield statute evidence of a complainant’s sexual conduct is not admissible unless used to show “the victim’s sexual conduct with the defendant or evidence of recent conduct of the victim alleged to be the cause of any physical feature, characteristic, or condition of the victim.” G. L. c. 233, § 21B. However, a judge may admit evidence of convictions for prostitution to show motive to lie or bias, consistent with Commonwealth v. Joyce, 382 Mass. 222 (1981).
Commonwealth v. Chase, 372 Mass. 736 (1977), was a departure from this court’s holding in Commonwealth v. West, 357 Mass. 245, 249 (1970), which stated that the words “conviction . . . may be shown” (emphasis in original) was an “option open to the party cross-examining the witness” and the judge had no discretion to exclude such evidence if a party wanted to introduce it. Until Commonwealth v. Maguire, 392 Mass. 466 (1984), which overruled Commonwealth v. West, supra, this court refused to review a judge’s exercise of that discretion. See Commonwealth v. Knight, 392 Mass. 192, 194 (1984), quoting Commonwealth v. Diaz, 383 Mass. 73, 80 (1981), and Commonwealth v. King, 391 Mass. 691, 695 (1984).
The rape-shield statute refers only to “specific instances of a victim’s sexual conduct” (emphasis added). G. L. c. 233, § 21B.
The three Justices’ opinion highlights the policy rationale for excluding evidence of a victim’s prior sexual conduct in a rape trial. Ante at 621-622. See Commonwealth v. Joyce, supra at 227; Commonwealth v. McKay, 363 Mass. 220, 227 (1973) (evidence of victim’s prior instances of intercourse inadmissible); Commonwealth v. Vandenhecke, 248 Mass. 403, 404 (1924) (fact that female witness is prostitute inadmissible to impeach her). I do not disagree with the holdings of these cases. The latter two are, however, not on point in this case, which concerns the use of prior convictions for prostitution to impeach a witness’s general credibility.