I concur in the result reached in the lead opinion and in its reasoning except for one point of law that is unnecessary to the result obtained. I also disagree with the concurring opinion, which also discusses a point of law that is unnecessary to the result. I write separately out of concern that these points of law, which could easily be omitted from the opinion, are wrongly decided and will cause unnecessary confusion in the adjudication of child support cases in the trial courts. Moreover, a rejoinder to the concurring opinion is necessary because it erroneously suggests the district attorney has violated the law.
My difference with the lead opinion is in its assertion, made without analysis, that “The ‘obligated’ parent referred to in [subdivision (e) of Civil *514Code section 4720] is the noncustodial parent from whom support is sought.” (Maj. opn., p. 509.) (All further statutory references are to the Civil Code unless otherwise noted.) I think the “obligated parent” is any parent with a legal obligation to support the child, regardless of whether the parent has physical custody.
Subdivision (e) of section 4720 is set out in the margin.1 Read in its entirety, the subdivision makes clear that an “obligated parent” is any parent with a legal obligation to support the child and does not depend on physical custody. Thus, the statute says, “A parent’s first and principal obligation is to support his or her minor children according to the parent’s circumstances and station in life.” Clearly this language does not single out the noncustodial parent as the only parent obligated to support the parents’ child. Rather, each parent is so obligated.
At one point, subdivision (e) of section 4720 facially suggests it is referring only to the noncustodial parent because it says the income of a parent’s subsequent spouse or nonmarital partner can be considered for ascertaining the parent’s disposable income “and therefore his or her ability to pay more than the mandatory minimum child support award established by this chapter.” (Italics added.) Ordinarily, custodial parents do not “pay” child support to themselves. Consequently, this reference, read in isolation, suggests the statute refers only to the noncustodial parent.
However, we have an obligation to construe the term “pay” in the context of the entire statutory scheme of which it is a part. (See People v. Woodhead (1987) 43 Cal.3d 1002, 1008 [239 Cal.Rptr. 656, 741 P.2d 154].) Section 4722 (pertinent portions of which are set out in the margin)2 makes *515clear that the Agnos Act does not use the term “pay” in the literal sense of having money change hands. Rather, section 4722 sets forth methods by which, “Each parent’s ability to pay a minimum mandatory amount of child support, . . .” is ascertained. Under section 4722, the ability of both the custodial and noncustodial parent to “pay” child support is calculated. “Pay” means “contribute to.” Subdivision (e) of section 4720 says the income of either parent’s subsequent spouse or nonmarital partner may be considered in determining that parent’s disposal income and therefore his or her ability to contribute to more than the mandatory minimum child support award.3 The income of the subsequent spouse of the custodial parent can therefore be considered for the purpose set forth in the statute.
In my view, this construction of the statutory language is the only one that satisfies our obligation to construe the statute to achieve a reasonable result and avoid absurdity. (See Dyna-Med, Inc. v. Fair Employment & Housing Com. (1987) 43 Cal.3d 1379, 1392 [241 Cal.Rptr. 67, 743 P.2d 1323].) Subdivision (e) of section 4720 is the only portion of the Agnos Act expressly authorizing a trial court to consider the earning capacity of a subsequent spouse in the computation of child support. Even putting aside constitutional equal protection concerns, why would the Legislature intend that only the income of the noncustodial subsequent spouse be considered in setting child support? Does this mean that if the custodial parent remarries a billionaire who lavishes untold wealth upon the parent and pays all the parent’s basic living expenses, the court cannot consider this fortuity of riches in determining the appropriate amount of child support, above the statutory minimum, to be contributed by each parent? Why would the Legislature wish such a state of affairs?
Even though subdivision (e) of section 4720 authorizes the trial court to consider the income of the subsequent spouse of a custodial parent, used to pay the parent’s basic living expenses, mother still loses in this case. As the lead opinion points out, both subdivision (e) of section 4720 and subdivision (e) of section 4721 authorize the court to consider such income only for the *516purpose of setting a child support award above the statutory minimum. Mother’s obligation here is to pay the statutory minimum award, the calculation of which is made without regard to the income of father’s new wife.
The concurring opinion wrongly lambastes the district attorney for representing father. Welfare and Institutions Code section 11475.1 plainly authorizes the representation and may require it.4 (Further references to section 11475.1 are to this statute.)
The concurring opinion argues section 11475.1 “contemplates the implication of the district attorney’s services in cases of need or when [AFDC] is involved.” (Conc. opn., p. 512.) However, it is clear that receipt of AFDC is not a precondition for the district attorney’s enforcement services. The statute expressly provides to the contrary. The statute gives the district attorney “responsibility for promptly and effectively enforcing child and *517spousal support obligations . . . (§ 11475.1, subd. (a).) This responsibility exists when the child is receiving public assistance, and “when requested to do so by the individual on whose behalf the enforcement efforts will be made when the child is not receiving public assistance." (Ibid, italics added.) The statute expressly commands the county to undertake an outreach program to inform the public that the district attorney’s enforcement service is available to persons not receiving public assistance. (Ibid.) The county must post notices informing the public “that child and spousal support enforcement services are provided to all individuals whether or not they are recipients of public social services.” (Ibid.)
Nor does section 11475.1 condition the district attorney’s services on a showing of financial hardship or “need.” The statute says the district attorney “shall” take appropriate action in non-AFDC cases when requested to do so by the individual on whose behalf enforcement will be sought. (See fn. 4, ante.) I need not reach the question whether this language mandates representation upon request in all non-AFDC cases or whether the statute preserves a traditional measure of “prosecutorial” discretion. For present purposes, it is sufficient to note that a showing of “need” is not a statutory prerequisite to the district attorney’s furnishing services.
The concurring opinion also argues that the district attorney’s services are available “to establish paternity and enforce prior orders or secure a temporary order in the first instance when prior proceedings relative to the spouses or child and parents have not been undertaken.” (Cone, opn., p. 512.) While this is trué, the statute contains no language of limitation precluding the district attorney from obtaining a child support order where, as here, a prior order has been entered in an action for dissolution of marriage but the order wrongfully fails to provide for payment of child support by the noncustodial parent. Section 11475.1 empowers the district attorney “to establish or enforce support obligations.” (See fn. 4, ante.) The statute commands the district attorney to “take appropriate action.” (Ibid.) Surely this includes obtaining a child support order in an existing action. The only limitation on the method of enforcement I can find in the statute is: “This responsibility [for enforcement of support obligations] applies to spousal support only where the spousal support obligation has been reduced to an order of a court of competent jurisdiction.” (§ 11475.1, subd. (a), italics added.) The statute thus envisions that the district attorney should enforce spousal support only where the spouse has first obtained an order. By its omission of any reference to child support in this sentence, the statute contemplates that the district attorney may obtain original child support orders, since the expression of certain things in a statute necessarily involves *518exclusion of other things not expressed.5 (Dyna-Med, Inc. v. Fair Employment & Housing Com., supra, 43 Cal.3d at p. 1391, fn. 13.) Although subdivision (a) of section 11475.1 allows a district attorney to obtain an order for temporary child support, the applicable language is language of authorization, not limitation. Nothing in the statute says the district attorney may obtain original orders only if they are temporary orders.
Assume, for example, father and mother dissolve their marriage and mother gets physical custody of child. At the time of dissolution, father is disabled and unable to contribute to child support. The judgment dissolving the marriage so provides. Five years later, mother learns father has recovered from his disability, is employed, and is able to pay child support. Mother is employed as a sales clerk and is not receiving public assistance. Upon mother’s request, can the district attorney represent her in an attempt to get child support from father? In my view, under section 11475.1 the answer is “yes.”
The district attorney did not act unlawfully in representing the father in this case.
Section 4720, subdivision (e) states: “It is the intention of the Legislature that the courts shall adhere to the principles set forth in this chapter and shall depart from them only in exceptional circumstances. A parent’s first and principal obligation is to support his or her minor children according to the parent’s circumstances and station in life. In this regard, the Legislature recognizes that a parent’s circumstances and station in life are dependent upon a variety of factors, including his or her earned and unearned income; earning capacity; assets; and the income of his or her subsequent spouse or nonmarital partner, to the extent that the obligated parent’s basic living expenses are met by the spouse or other person, thus increasing the parent’s disposable income and therefore his or her ability to pay more than the mandatory minimum child support award established by this chapter. The court shall take into consideration the needs of the supported child or children in determining whether circumstances give rise to an increase or decrease in a child support award.”
Section 4722 states in pertinent part: “(a) The standard established pursuant to Section 11452 of the Welfare and Institutions Code, as adjusted by Section 11453 of the Welfare and Institutions Code, establishes a minimum family support level based on the number of eligible needy persons in the family.
“(b) Each parent’s ability to pay a minimum mandatory amount of child support, whether for a temporary or a permanent order, shall be determined in accord with the standards established by Section 11452 of the Welfare and Institutions Code, and prior to the computa*515tion of the spousal support liability, as follows: [¶] (1) The combined monthly net disposable income of both parents shall be multiplied by the following percentage factors: 18 percent for one child; 27 percent for two children; 36 percent for three children; 40 percent for four children; and an additional four percent for each child thereafter, up to a total of 10 children.
“(2) If the resulting amount is less than the AFDC standard for the number of children involved, the court shall find that the parents are unable to pay at the level of the children’s portion of the AFDC standard and shall set a minimum award according to the actual combined net income and the percentages set forth above.
“(3) If the resulting amount is at, or greater than, the AFDC standard for the same number of children, the court shall order a minimum award that equals the AFDC standard.” (Italics added.)
Under subdivision (d) of section 4722 both the custodial and noncustodial parents are ordered to contribute a proportionate share of the award.
Welfare and Institutions Code section 11475.1 provides in pertinent part: “(a) Each county shall maintain a single organizational unit located in the office of the district attorney which shall have the responsibility for promptly and effectively enforcing child and spousal support obligations and determining paternity in the case of a child born out of wedlock. The district attorney shall take appropriate action, both civil and criminal, to enforce this obligation when the child is receiving public assistance, and when requested to do so by the individual on whose behalf the enforcement efforts will be made when the child is not receiving public assistance. To the extent required by federal law, actions brought by the district attorney to establish or enforce support obligations in all cases, other than paternity cases or those cases involving complex issues, shall be completed within the following time limits: (1) 90 percent of the actions shall be completed within three months from the date of service; (2) 98 percent of the actions shall be completed within six months from the date of service; and (3) 100 percent of the actions shall be completed within 12 months from the date of service. As used in this section, ‘service’ means the service of process required by law for the particular proceeding. This responsibility applies to spousal support only where the spousal support obligation has been reduced to an order of a court of competent jurisdiction. In any action brought for modification or revocation of an order that is being enforced under Title IV-D of the Social Security Act, the effective date of the modification or revocation shall be as prescribed by federal law (42 U.S.C. Sec. 666(a)(9)), or any subsequent date. In any action brought or enforcement proceedings instituted by the district attorney pursuant to this section for payment of child or spousal support, an action to recover an arrearage in support payments may be maintained by the district attorney at any time within the period otherwise specified for the enforcement of a support judgment, notwithstanding the fact that the child has attained the age of majority. The county shall undertake an outreach program to inform the public that this service is available to persons not receiving public assistance. There shall be prominently displayed in every public area of every office of the units established by this section a notice, in clear and simple language prescribed by the Director of Social Services, that child and spousal support enforcement services are provided to all individuals whether or not they are recipients of public social services.
“In any action for child support brought by the district attorney in the performance of duties under this section, the district attorney may make a motion for an order effective during the pendency of that action, for the support, maintenance, and education of the child or children that are the subject of the action. This order shall be referred to as an order for temporary support. This order shall have the same force and effect as a like or similar order under the Family Law Act (Part 5 (commencing with Section 4000) of Division 4 of the Civil Code).”
Known to those at Yale Law School as the doctrine, “Expressio unius est exclusio alterius.”