— We accepted review of this case from Division One of the Court of Appeals, which affirmed the defendant’s conviction of four counts of first degree robbery. The sole issue before this court is whether two “stayed” California convictions were properly counted as a “strike” under the Persistent Offender Accountability Act (POAA), see RCW 9.94A.120. We hold that they were and affirm Lanyard Berry’s judgment and sentence to life imprisonment without the possibility of parole.
I
FACTS
A
Berry’s Prior California Convictions
In 1975, Berry was convicted in California of voluntary manslaughter (Count I) for shooting and killing Kathleen Williams, and of assault with intent to commit murder (Count II) and assault with a deadly weapon (Count III) for shooting Willie Earl Smith.1 During sentencing, the court and both counsel discussed California’s prohibition against multiple punishments for the same act under California Penal Code section 654.
The trial court orally ruled that both assaults “arose out of one act” and ordered that the judgment and sentence on Count II be temporarily “stayed” until the sentence on Count III was served or the judgment became permanent, at which time the stay would also become permanent. See *124Clerk’s Papers (CP) at 511-12.2 The trial court’s written ruling, however, contradicted its oral ruling. The trial court’s written judgment ordered that the sentences on both assault counts would be stayed until the sentence and conviction on the manslaughter count was served or became permanent.3 Berry appealed his convictions.
On appeal, the California Court of Appeal ordered that Berry’s voluntary manslaughter conviction be lowered to involuntary manslaughter. The remainder of Berry’s judgment and sentence, however, was otherwise affirmed.
On remand, the trial court modified Berry’s manslaughter conviction as ordered. The trial court, however, went further and modified the original stay provisions to be consistent with its original oral ruling. The trial court removed the stay on Count III and ordered that the stay on Count II should remain in effect until both Counts I and III were served or became permanent.4 Berry filed a writ of habeas corpus challenging the modification of the original stay provision.
In 1978, a different California trial court granted Berry’s writ and held that the amendments to the stay provisions “had no force and effect” because the original trial court had no jurisdiction to amend that part of the judgment. CP at *125553. Consequently, the original stay of both assault convictions remained in effect.
B
Berry’s “Persistent Offender” Sentencing
In 1997, Berry was convicted in Washington of four counts of first degree robbery. Following these convictions, the trial court sentenced Berry. In determining Berry’s criminal history under RCW 9.94A.120, the State conceded and the trial court found that Berry’s involuntary manslaughter conviction did not qualify as a prior strike because it was not comparable to a “ ‘most serious offense’ ” in Washington. CP at 607. The trial court, however, found that Berry’s 1985 robbery conviction qualified as a strike. The trial court also found that the two 1975 California assault convictions qualified as a single strike because they had never been set aside and because the one victim involved in both assault convictions was different from the victim involved in the manslaughter conviction. Based on this criminal history, Berry was sentenced as a “Persistent Offender” to life imprisonment without the possibility of parole. CP at 579-80, 608.
II
ANALYSIS
The first issue we address is whether the State could collaterally attack the stay provisions. We hold that the full faith and credit clause requires that our courts recognize the stay provisions as valid and binding. The next issue, therefore, is how these stayed convictions should be treated under Washington’s persistent offender statute. We hold that the trial court properly considered them as a prior strike in sentencing Berry as a persistent offender.
*126A
Collateral Attack on Out-of-State Convictions
1. California’s Stay Procedure
California Penal Code section 6545 prohibits multiple punishments, but not multiple convictions, for two or more offenses arising from the same act or indivisible course of conduct. People v. Pearson, 42 Cal. 3d 351, 721 P.2d 595, 599-600, 228 Cal. Rptr. 509 (1986) (citing cases). Section 654 does not apply, however, where a single act or course of conduct is committed against separate victims. People v. Arndt, 76 Cal. App. 4th 387, 90 Cal. Rptr. 2d 415, 421-22 (1999) (citing cases).
To promote the purposes of section 654, the California courts developed a procedure where the courts “stay” the execution of sentences for all but one conviction arising out of each act or indivisible course of conduct.6 The purpose of California’s stay procedure is to avoid improper multiple punishments, while also avoiding leaving a defendant without any convictions if the trial court dismissed the stayed convictions at sentencing and if the nonstayed convictions were later reversed on appeal. Pearson, 721 P.2d at 600-01. A stayed sentence becomes permanently stayed when the defendant’s sentences on any nonstayed convictions have been served. Pearson, 721 P.2d at 600.7
*127In California, permanently stayed convictions generally may not be used to enhance future sentences or in any way used to disadvantage a defendant. Pearson, 721 P.2d at 601. An exception exists where the Legislature explicitly declares that stayed convictions may be used to enhance future sentences. California’s “Three Strikes” law explicitly provides such a declaration. See People v. Benson, 18 Cal. 4th 24, 954 P.2d 557, 560-62, 74 Cal. Rptr. 2d 294 (1998) (citing, inter alia, Cal. Penal Code § 667(d)(1)(B); Cal. Penal Code § 1170.12). Consequently, Berry’s stayed convictions could be used as strikes under California law. See Benson, 954 P.2d at 560-62.
2. Full Faith and Credit
The State argues that because Washington courts do not recognize clearly erroneous convictions, we should not recognize the stay provisions that were improperly imposed under California law. The assault convictions involved a victim who was different from the victim involved in the manslaughter conviction. Therefore, we agree that the California trial court appears to have mistakenly stayed both assault convictions. However, we hold that the full faith and credit clause requires that we recognize the stays as valid.
“Judgments, including criminal convictions of sister states, are generally accorded full faith and credit and their validity may not be collaterally attacked,” absent constitutional infirmity. State v. Rinier, 23 Wn. App. 102, 105, 595 P.2d 43 (1979). “The Full Faith and Credit Clause provides a means for ending litigation by putting to rest matters previously decided between adverse parties in any state or territory of the United States.” In re Estate of Tolson, 89 Wn. App. 21, 29, 947 P.2d 1242 (1997). A valid *128foreign judgment may be collaterally attacked only if the court lacked jurisdiction or constitutional violations were involved. Absent these grounds, “ ‘a court of this state must give full faith and credit to the foreign judgment and regard the issues thereby adjudged to be precluded in a Washington proceeding.’ ” In re Tolson, 89 Wn. App. at 30 (quoting In re Estate of Wagner, 50 Wn. App. 162, 166, 748 P.2d 639 (1987)).
We find that the full faith and credit clause applies with full force here. There is no claim that the conviction is invalid in California, or that the California court did not have jurisdiction or committed constitutional error. Rather, the only claim is that the California court mistakenly applied California law.
We note that this case is distinguishable from Washington decisions that did not recognize out-of-state judgments. See State v. Carver, 113 Wn.2d 591, 602-03, 781 P.2d 1308, 789 P.2d 306 (1989) (full faith and credit clause not violated where custody statutes authorized Washington court to modify out-of-state custody decree). Here, there was no statutory authority to modify the • California judgment. Thus, the basic tenet that foreign judgments control in Washington court proceedings applies. Consequently, we find that Berry’s assault convictions, including, the stay provisions, must be afforded full faith and credit.
The dissent contends that “[i]f we are to give full faith and credit to the California judgment of conviction we must likewise give full faith and credit to the legal limitations on the use or meaning intrinsic to that stayed conviction.” Dissent at 134 (emphasis omitted). This statement, however, is clearly contrary to the repeated pronouncements of the United States Supreme Court.
While the full faith and credit clause applies in full force to judgments, its effect is lessened when the statutes or judicial decisions of another forum are at issue. Baker v. General Motors Corp., 522 U.S. 222, 232-33, 118 S. Ct. 657, 139 L. Ed. 2d 580 (1998). “The Full Faith and Credit Clause does not compel ‘a state to substitute the statutes of other *129states for its own statutes dealing with a subject matter concerning which it is competent to legislate.’ ” Id. (quoting Pacific Employers Ins. Co. v. Industrial Accident Comm’n, 306 U.S. 493, 501, 59 S. Ct. 629, 83 L. Ed. 940 (1939)).8
In fact, it is under this doctrine that a California court, the forum to which the dissent would defer, recently held that even if an Arizona statute legally restored a convicted felon’s right to possess a firearm, full faith and credit did not require California to follow Arizona’s law. See People v. Shear, 71 Cal. App. 4th 278, 288-89, 83 Cal. Rptr. 2d 707 (1999) (affirming firearm possession conviction under California law). The California court chose to apply its own law in part because “[i]t is 'the expression of [California’s] domestic policy, in terms declared to be exclusive in its application to persons and events within the state.’ California’s ‘significant contact’ with defendant, a California resident, creates a ‘ “state interest [], such that choice of its law is neither arbitrary nor fundamentally unfair.” ’ ” Shear, 71 Cal. App. 4th at 288 (alterations in original) (quoting Pacific Employers Ins. Co., 306 U.S. at 502-03; Phillips Petroleum Co. v. Shutts, 472 U.S. 797, 818, 105 S. Ct. 2965, 86 L. Ed. 2d 628 (1985)).
Shear amply demonstrates that Washington law may be applied to a petitioner who is a Washington resident and who has committed his most recent offense within this state. All that full faith and credit requires is that Washington respect California’s judgment of conviction, which we have done. The next issue, therefore, becomes whether Berry’s stayed convictions count as strikes under the POAA.
*130B
“Stayed” California Convictions as “Strikes” under the Persistent Offender Accountability Act
If a defendant is found to be a “persistent offender” in Washington under the POAA, the court must sentence the defendant to life in prison without the possibility of parole. RCW 9.94A. 120(4). A “persistent offender” is defined as (1) someone who is convicted of a “most serious offense” and (2) who has previously been convicted on at least two separate occasions, (3) in this state or elsewhere, (4) of felonies which would be considered most serious offenses under RCW 9.94A.030(23) and that (5) would be included in the offender score under RCW 9.94A.360. State v. Morley, 134 Wn.2d 588, 603, 952 P.2d 167 (1998) (citing former RCW 9.94A-030(27)(a)(ii) (1996)).
It is undisputed that Berry is being sentenced for a “most serious offense” — first degree robbery. It is also undisputed that Berry has been previously convicted on at least two separate occasions in this state or elsewhere. Finally, it is undisputed that the assault convictions, absent the stay provisions, would be included in Berry’s offender score under RCW 9.94A.360.9 The only issue is whether the assault convictions involve “felonies that under the laws of this state would be considered most serious offenses . . . .” Former RCW 9.94A.030(27)(a)(ii).
To determine whether out-of-state convictions qualify as most serious offenses under Washington law, a “comparability” analysis is conducted. The goal is to match the out-of-state crime to the comparable Washington crime *131and “to treat a person convicted outside the state as if he or she had been convicted in Washington.” State v. Cameron, 80 Wn. App. 374, 378, 909 P.2d 309 (1996) (citing case).10
The first step in the comparability analysis is to identify any comparable Washington offenses by comparing the elements of the out-of-state crime with the elements of the potentially comparable Washington crimes. E.g., Cameron, 80 Wn. App. at 378-79 (citing case). If comparable offenses are found, the court decides which is the most comparable offense and determines its classification under Washington law. See, e.g., Cameron, 80 Wn. App. at 378-79. After determining its classification under Washington law, the court treats the out-of-state conviction “as if it were a conviction for the comparable Washington offense.” Cameron, 80 Wn. App. at 378-79 (citing case).
Berry argues that the traditional comparability analysis is inapplicable. Berry urges that, in addition to comparing the elements of comparable crimes, the court should also compare the “legal effect” of California’s stay procedure to similar procedures in Washington. Br. of Appellant at 32. Under Berry’s analysis, the stayed assault convictions are the equivalent of merged, dismissed or vacated convictions. We disagree.
Berry incorrectly characterizes the stayed assaults as dismissed or vacated under California law. There is no evidence that the assault convictions were ever dismissed or vacated. Furthermore, Berry’s merger argument requires a postconviction comparability analysis. Washington’s comparability analysis, however, focuses on the conviction and the elements of the offense and not on the sentencing or postjudgment remedies which do not result in either a dismissal or vacation.11
*132We have not previously included postconviction procedures under the comparability analysis and find that expanding the comparability analysis beyond an elemental analysis would unnecessarily complicate an already difficult process. Cf. Morley, 134 Wn.2d at 596 (“Nothing in the SRA [Sentencing Reform Act of 1981] states or implies that a sentencing court must conduct the tedious task of comparing out-of-state criminal procedures to in-state procedures.”). Therefore, we find that the assault convictions remain valid “convictions” as that term is defined by the POAA. See ROW 9.94A.030(9).
Ill
CONCLUSION
The goal of the POAA is to appropriately punish repeat violent offenders, including those with out-of-state convictions for violent offenses. This goal is served by including valid out-of-state convictions that have not been dismissed or vacated, that satisfy the standard comparability analysis, and that meet our most serious offense criteria. Consequently, we hold that the trial court properly considered Berry’s stayed assault convictions as a strike under the POAA and affirm Berry’s sentence for life without parole.
Guy, C.J., Smith, Johnson, Madsen, Alexander, and Talmadge, JJ., and Kennedy, J. Pro Tern., concur.
In 1985, Berry was also convicted of robbery in California. However, there is no challenge regarding that conviction here.
The trial court specifically stated that:
[T]he judgment in and sentence pronounced on count two [the first assault count] be suspensed [sic] in the judgment on count three [the second assault count], the service of the sentence imposed thereon is completely served or the judgment becomes final and the stay will become permanent.
CP at 511-12.
The trial court specifically stated that:
[Execution of the sentence on Counts two and three be stayed until the sentence and conviction on Count one has been served or becomes permanent.
CP at 458.
The trial court specifically stated that:
[E]xecution on the sentence on Count two be stayed until the sentence and conviction on Counts one and three has been served or becomes permanent.
CP at 695-96.
The relevant portion of California Penal Code section 654(a) states:
An act or omission that is punishable in different ways by different provisions of law shall be punished under the provision that provides for the longest potential term of imprisonment, but in no case shall the act or omission be punished under more than one provision.
California’s stay procedure is clearly distinct from Washington’s. Compare Pearson, 721 P.2d at 599-600 (“stay” serves to comply with prohibition against multiple punishments) with In re Koome, 82 Wn.2d 816, 818, 514 P.2d 520 (1973) (a “stay order” in Washington is recognized as the “temporary suspension of the regular order of proceedings in a cause .. ..” (quoting Black’s Law Dictionary 1583 (4th ed. rev. 1968))).
Pearson recommended that to avoid confusion in future cases involving stayed *127convictions, the stayed convictions should be formally dismissed after the defendant fully completes his sentence on the nonstayed convictions. Pearson, 721 P.2d at 602 n.4. As is evident here, however, California courts have not always followed Pearson’s advice. See, e.g., People v. Escobar, 45 Cal. App. 4th 477, 482, 53 Cal. Rptr. 2d 9 (1996) (court found reversal of properly stayed count “unnecessary”).
See also Phillips Petroleum Co. v. Shutts, 472 U.S. 797, 822, 105 S. Ct. 2965, 86 L. Ed. 2d 628 (1985); Alaska Packers Ass’n v. Industrial Accident Comm’n, 294 U.S. 532, 55 S. Ct. 518, 79 L. Ed. 1044 (1935); Bradford Elec. Light Co. v. Clapper, 286 U.S. 145, 52 S. Ct. 571, 76 L. Ed. 1026, 82 A.L.R. 696 (1932), overruled in part on other grounds by Crider v. Zurich Ins. Co., 380 U.S. 39, 85 S. Ct. 769, 13 L. Ed. 2d 641 (1965).
To avoid potential confusion, we briefly note that issues raised in our recent decision in State v. Cruz, 139 Wn.2d 186, 193, 985 P.2d 384 (1999), concerning whether a conviction has “washed out” are not involved here. In addition to Berry’s failure to properly raise this issue, this issue is nugatory because neither Berry’s first degree nor second degree assault convictions would have “washed out.” See RCW 9.94A.360(2) (Class A prior felony convictions “shall always be included in the offender score.” Class B prior felony convictions shall be included in the offender score unless the offender has spent 10 years conviction-free since the last date of release from confinement.); RCW 9A.36.011 (first degree assault is a class A felony); RCW 9A.36.021 (second degree assault is a class B felony).
The “comparability” analysis under RCW 9.94A.120 is the same as that for determining whether a foreign conviction is included in a defendant’s offender score. State v. Mutch, 87 Wn. App. 433, 437, 942 P.2d 1018 (1997).
See Cameron, 80 Wn. App. at 378-79 (court focuses on comparing elements of out-of-state and in-state crimes); RCW 9.94A.230(3) (vacated convictions not included in criminal history); see also Johnson v. Mississippi, 486 U.S. 578, *132585-87, 108 S. Ct. 1981, 1986-88, 100 L. Ed. 2d 575 (1988) (discussing impropriety of using reversed conviction in habitual offender sentencing) (citing cases).