I concur with the majority opinion to the extent that it reverses the order vacating the 1978 judgment of paternity. I respectfully dissent, however, from the majority’s holding that defendant may collaterally attack that judgment. In my view, we should conclusively presume the validity of the 1978 judgment.
A cognovit clause, or confession of judgment, is a device by which a debtor consents in advance to a judgment entered without notice and a hearing. (D. H. Overmyer Co. v. Frick Co. (1972) 405 U.S. 174, 176 [31 L.Ed.2d 124, 128, 92 S.Ct. 775].) While the United States Supreme Court has declined to hold that this device is per se violative of due process, that court has suggested that the result might be different in certain cases, where, for example, a great disparity of bargaining power exists. (Id., at pp. 187-188 [31 L.Ed.2d at pp. 135-136].)
In April 1978, based upon our observation that confessions of judgment were typically executed by debtors with little understanding of their significance and little bargaining power to exert, a majority of this court held the California confession statutes (former Code Civ. Proc., §§ 1132-1134) constitutionally deficient for their failure to require a prejudgment determination that the debtor voluntarily, knowingly and intelligently waived his rights to notice and a hearing. (Isbell v. County of Sonoma (1978) 21 Cal.3d 61, 64-66 [145 Cal.Rptr. 368, 577 P.2d 188].) The Legislature has since amended Code of Civil Procedure section 1132 to allow judgment by confession only upon certification by the debtor’s independent counsel that he has advised the debtor regarding his waiver of his various rights and defenses and has recommended the confession of judgment procedure. (Stats. 1979, ch. 568, § 1, p. 1795.)
Welfare and Institutions Code section 11476.1, as it existed in 1978, provided in relevant part: “In any case where the district attorney has undertaken enforcement of support, the district attorney may enter into an agreement with the noncustodial parent, on behalf of the custodial parent, a minor child, or children, for the entry of a judgment determining paternity, if applicable, and for periodic child support payments based on the noncustodial parent’s reasonable ability to pay. Prior to entering into this agreement, the noncustodial parent shall be informed that a judgment will be entered based on the agreement. The clerk shall file the agreement without the payment of any fees or charges. The court shall enter judgment thereon without action.”
In 1979, an appellate court invalidated an agreement executed pursuant to the foregoing provision because the agreement did not on its face reflect *494a knowing, voluntary and intelligent waiver of the due process rights of the noncustodial parent and because the statute itself did not require a prejudgment determination of whether such a waiver had occurred. (County of Ventura v. Castro (1979) 93 Cal.App.3d 462, 469-471 [156 Cal.Rptr. 66].) Because the statute directed that judgment be entered without such a prior judicial determination, the Castro court held it to be constitutionally infirm under Isbell. (Id., at pp. 472-473.)
In 1980, the Legislature responded to Castro by amending section 11476.1 to require either (1) a certification by the noncustodial parent’s counsel that he advised his client as to his rights and that the client agreed to entry of judgment, or (2) a judicial determination by the judge before whom the proposed judgment is pending that the noncustodial parent has been advised of his due process rights and has willingly, knowingly and intelligently waived them. (Stats. 1980, ch. 682, § 1, p. 2068.)
County urges that the trial court herein, in essence, has applied Castro and new section 11476.1 retroactively by its determination that the judgment must be set aside for lack of a knowing and intelligent waiver by Soto of his rights to notice and a hearing. County stresses that if Castro is applied retroactively numerous other judgments entered pursuant to former section 11476.1, and familial relationships established in reliance thereon, would be seriously and unnecessarily disturbed.
a.) Applicability of Isbell
The issue of Castro’s retroactivity would be rendered moot if Isbell established a constitutional principle requiring a prejudgment waiver determination for all stipulated judgments. Isbell does contain some broad language to the effect that “[a] judgment based solely upon an executed confession is constitutionally defective because that confession is insufficient to demonstrate that the debtor has voluntarily, knowingly, and intelligently waived his due process rights.” (Isbell, supra, 21 Cal.3d at p. 66, italics omitted.) This statement, however, was much broader than necessary to resolve the issues raised in Isbell, and we did not consider the very different factual setting involved here.
Isbell concerned the enforceability of confessions of judgment negotiated between commercial debtors and creditors, not the enforceability of child support or paternity judgments entered pursuant to former section 11476.1 of the Welfare and Institutions Code. Indeed, we carefully noted in Isbell that “We hold here only that sections 1132, subdivision (a), 1133, and 1134 of the Code of Civil Procedure enact an unconstitutional procedure. The validity of judgments entered pursuant to stipulation or agreement under the *495authority of other statutes or rules of court is not before us in the present case, and we do not imply that such judgments are void. ” (21 Cal.3d at p. 75, fn. 9, italics added.)
We stressed in Isbell that confessions of judgment executed under former Code of Civil Procedure sections 1132 through 1134 “have not found widespread use in California.” (Id., at p. 74.) In contrast, County notes that (1) in its own jurisdiction alone more than 31,000 paternity or child support judgments such as the one at issue here have been entered pursuant to former section 11476.1; (2) it has collected approximately $30 million thereunder for the benefit of the children involved; and (3) it estimates that $58 million has been collected statewide under similar paternity and child support judgments. An amicus estimates that 80,000 judgments were entered statewide pursuant to this section between the statute’s enactment in 1975 and the Castro decision in 1979.
Thus, unlike the confessions of judgment considered in Isbell, stipulated judgments in paternity and child support cases have been widely used and relied upon by the counties on behalf of custodial parents. Even in Isbell we gave only limited retroactive effect to our decision in view of the likely payment of substantial sums of money in reliance on such judgments, as well as the confusion which would have resulted from automatically voiding such judgments. (Ibid.) Here the size of the sums involved, the prevalence of the agreements, the reliance on their validity, and the potential confusion which would result from calling them in question are far greater than in Isbell. In addition, unlike a confession of judgment in a commercial context, the stipulated child support agreements authorized by section 11476.1 of the Welfare and Institutions Code are subject to future modification upon a proper showing. (See Civ. Code, § 4700, subd. (a).) The availability of periodic court-ordered modification in child support cases amply distinguishes the situation in Isbell and affords an important due process safeguard which is unavailable to ordinary commercial debtors.
We chose in Isbell to make then-existing (pre-1978) confessions of judgment voidable upon a debtor’s application for hearing, unless the creditor could establish file validity of the debtor’s waiver of constitutional rights. (Id., at p. 75.) Consequently, if Isbell controls here, presumably all stipulated paternity and child support judgments entered between the dates of Isbell and Castro, including the judgment at issue here, would be absolutely void, and those executed prior to Isbell would be voidable, depending on the evidence adduced at hearings attacking such judgments. I conclude that in light of the dire and sweeping consequences of a contrary ruling and a court’s continuing opportunity to modify child support obligations based upon financial ability, the generalizations in Isbell suggesting that a confes*496sion of judgment is unconstitutional per se should be deemed limited to the normal commercial debtor-creditor relationships which we examined in Is-bell.
b.) Retroactivity of Castro
Because I conclude that Isbell did not establish a constitutional principle invalidating all stipulated judgments, I next consider the retroactivity of Castro itself.
Although Castro left unresolved the issue of the retroactivity of its decision (93 Cal.App.3d at p. 474, fn. 2), this issue was subsequently decided in County of Los Angeles v. Superior Court (1981) 123 Cal.App.3d 988 [177 Cal.Rptr. 70]. After considering various approaches to the retroactivity issue, the Court of Appeal relied upon our analysis in Salas v. Cortez (1979) 24 Cal.3d 22 [154 Cal.Rptr. 529, 593 P.2d 226], and concluded that Castro should not be applied retroactively. (County of Los Angeles, supra, at pp. 992-993.)
In Salas, we determined that indigent defendants in paternity actions were entitled to legal representation, but we chose not to give our decision a retroactive effect which would invalidate earlier paternity judgments because “obligations, and, in some cases, familial relationships have been established” in reliance on those judgments. (Salas, supra, at p. 24.) Weighing the fairness and public policy factors affecting the retroactivity decision (see Li v. Yellow Cab Co. (1975) 13 Cal.3d 804, 829 [119 Cal.Rptr. 858, 532 P.2d 1226, 78 A.L.R.3d 393]), the County of Los Angeles court concluded that, as in Salas, there was a strong public interest in the finality of judgments under former section 11476.1 because financial obligations and familial relationships had been established thereby. (County of Los Angeles, supra, at pp. 992-993.)
I agree with the foregoing reasoning. Once family relationships have been formed, fathers, mothers, and their children must be permitted to rely on the legal finality of those relationships. Only a purely prospective application of Castro would protect paternity judgments entered pursuant to former section 11476.1.
The majority’s “voidable judgment” approach casts doubt upon thousands of paternity and support judgments and, as a practical matter, will encumber the enforcement of the underlying agreements through contempt proceedings because of invitations, as here, to challenge the validity of the judgment.
*497An additional unfortunate side effect of the majority’s holding is that it effectively extends beyond the long established statutory six-month limitation of Code of Civil Procedure section 473 the period within which judgments may be attacked for mistake, inadvertence, surprise, or excusable neglect.
In the interest of preserving the finality of judgments and respecting the parties’ reliance thereon, particularly where familial relationships have been established, I conclude that Castro should be applied prospectively only in paternity and child support contexts.
Mosk, J., and Kaus, J., concurred.
The petitions of both parties for a rehearing were denied March 29, 1984. Mosk, J., and Kaus, J. were of the opinion that the petitions should be granted.