with whom Mr. Justice Brennan joins, dissenting.
Because the Court today ignores a fundamental rule for interpreting the Social Security Act, I must respectfully dissent. As we said in Townsend v. Swank, 404 U. S. 282, 286 (1971), “in the absence of congressional authorization for the exclusion clearly evidenced from the Social Security Act or its legislative history, a state *424eligibility standard that excludes persons eligible for assistance under federal AFDC standards violates the Social Security Act and is therefore invalid under the Supremacy Clause.” See also King v. Smith, 392 U. S. 309 (1968); Carleson v. Remillard, 406 U. S. 598, 600 (1972). The New York Work Rules fall squarely within this statement; they clearly exclude persons eligible for assistance under federal standards, and it could hardly be maintained that they did not impose additional conditions of eligibility.1 For example, under federal standards, it is irrelevant to a determination of eligibility that a recipient has or has not filed every two weeks a certificate from the local employment office that no suitable employment opportunities are available, yet under the Work Rules, a recipient who fails to file such a certificate is “deemed” to have refused to accept suitable employment, and so is not eligible for assistance. N. Y. Soc. Serv. Law §131 (4) (a) (Supp. 1971-1972).2 Thus, according to the rules of interpretation we have heretofore followed, the proper inquiry is whether the Social Security Act or its legislative history clearly shows congressional authorization for state employment requirements other than those involved in WIN.3
*425The answer is that neither the Act nor its legislative history shows such an authorization. The only relevant work-related conditions of eligibility in the Act are found at 42 U. S. C. § 602 (a) (19) (1970 ed., Supp. I). In addition to exempting certain persons from registration for and participation in WIN,4 the Act permits States to *426disregard the needs of persons otherwise eligible for assistance who “have refused without good cause to participate under a work incentive program . . . or . . . to accept employment in which he is able to engage.” 42 TJ. S. C. § 602 (a) (19) (F) (1970 ed., Supp. I). The Act thus makes actual refusal to participate in a WIN Program or to accept employment a permissible ground for denying assistance. In contrast, New York has adopted the none-too-subtle technique of “deeming” persons not to have accepted employment because they have not, for example, obtained a certain certificate from the local employment office every two weeks. “Deeming” is a familiar legal device to evade applicable requirements by saying that they have been satisfied when they have not in fact been satisfied. But the federal requirement, which the State may not alter without clear congressional authorization,5 requires an actual refusal to participate in a WIN Program or to accept employment, not a refusal to participate in some other program or a fictitious refusal of employment.6
The legislative history of the Social Security Act confirms this interpretation, for whenever Congress legislated *427with respect to work requirements, it focused on actual refusals to accept employment or to participate in certain special programs clearly authorized by Congress. At no time has Congress authorized States to adopt other work-referral programs or to make refusal to participate in such programs a condition of eligibility, even under the guise of “deeming” such a refusal a refusal to accept employment.
At its inception, the program of Aid to Dependent Children was designed to lessen somewhat the burden of supporting such children. The program provided assistance to children who had been deprived of parental support by reason of the absence of a parent. 49 Stat. 629 (1935). Assistance was provided to supply the needs of such children, thus “releas [ing the parent] from the wage-earning role.” H. R. Doc. No. 81, 74th Cong., 1st Sess., 30 (1935). See also H. R. Rep. No. 615, 74th Cong., 1st Sess., 10 (1935). Thus, the program’s purposes were in many ways inconsistent with a requirement that the parent leave the home to accept employment. Yet, in operation, the original program failed to provide sufficient inducement for the parent to remain at home, since the amount of assistance was measured solely by the child’s needs. In order further to relieve the pressures on the parent to leave the home and accept work, Congress amended the Act in 1950 so that the aid would include payments “to meet the needs of the relative with whom any dependent child is living.” 42 U. S. C. § 606 (b)(1).
Until 1961, then, the sole emphasis of the Social Security Act’s provisions for assistance to dependent children was on preserving the integrity of the family unit.7 *428In that year, Congress expanded the definition of dependent child to include children deprived of parental support by reason of the unemployment of a parent. 42 U. S. C. § 607. Families with two parents present could, for the first time, receive assistance, and one parent could leave the home to work without impairing the integrity of the family unit. Congress therefore required States participating in the program for aid to families with an unemployed parent to deny assistance under this provision to individuals who refused to accept bona fide offers of employment. Pub. L. 87-31, 75 Stat. 76 (1961). Refusal of actual offers of employment was clearly the contemplated condition. See S. Rep. No. 165, 87th Cong., 1st Sess., 3 (1961). Congress then developed this concept, permitting States to establish “Community Work and Training Programs” of work on public projects, Pub. L. 87-543, § 105, 76 Stat. 186, rendered inapplicable by Pub. L. 90-248,81 Stat. 892. Refusal to accept a work assignment on such a project without good cause would be a ground for denial of public assistance. See H. R. Rep. No. 1414, 87th Cong., 2d Sess., 15 (1962).
When Congress established WIN, it did not abandon its previous policies. Recipients of public assistance could be required only to accept bona fide offers of employment or placement in specified programs. There is no indication whatsoever in the legislative history that Congress intended to permit States to deny assistance because potential recipients had refused to participate in programs not supervised by the Secretary of Labor, as WIN Programs are. The parameters of the WIN Program were designed to accommodate Congress' dual interests jin guaranteeing the1 integrity of the family and in maximizing the potential for employment of recipients of public assistance. Without careful federal supervision, of the sort contemplated by the delegation to *429the Secretary of Labor to establish testing and counseling services and to require that States design employ-ability plans, 81 Stat. 885, state work programs might upset the accommodation that Congress sought. The Work Incentive Program was thus a carefully coordinated system, whose individual parts fit into an integrated whole. It is hardly surprising that Congress did not expressly or impliedly authorize States to develop independent work programs, since the WIN Program represented Congress’ recognition that such programs had to be kept under careful scrutiny if the variety of goals Congress sought to promote were to be achieved.8 I believe that the Court seriously misconceives the purposes of the federal programs of public assistance, in its apparent belief that Congress had the sole purpose of promoting work opportunities, a purpose that precluding additional state programs would negate. Ante, at 418-420.
*430Instead, Congress has consistently indicated its desire to adopt programs that will enhance the employability of recipients of public assistance while maintaining the integrity of families receiving assistance. A work-referral program can do this only if it is regulated, both as to the persons required to participate and as to the terms on which they must participate. And Congress has consistently recognized that such regulation requires close federal supervision of work programs. In my view, this course of legislation, which is not mentioned by the Court, is neither “ambiguous,” “fragmentary,” nor “peripheral,” ante, at 415, 416, 417. No matter how it is viewed, however, one cannot fairly say that the Social Security Act or its legislative history clearly evidences congressional authorization for making participation in state work programs a condition of eligibility for public assistance.9
*431The policy of clear statement10 in Townsend serves a useful purpose. It informs legislators that, if they wish to alter the accommodations previously arrived at in an Act of major importance, they must indicate clearly that wish, since what may appear to be minor changes of narrow scope may in fact have ramifications throughout the administration of the Act. A policy of clear statement insures that Congress will consider those ramifications,11 but only if it is regularly adhered to.
Finally, it is particularly appropriate to require clear statement of authorization to impose additional conditions of eligibility for public assistance. Myths abound in this area. It is widely yet erroneously believed, for *432example, that recipients of public assistance have little desire to become self-supporting. See, e. g., L. Goodwin, Do the Poor Want to Work? 5, 51-52, 112 (1972). Because the recipients of public assistance generally lack substantial political influence, state legislators may find it expedient to accede to pressures generated by misconceptions. In order to lessen the possibility that erroneous beliefs will lead state legislators to single out politically unpopular recipients of assistance for harsh treatment, Congress must clearly authorize States to impose conditions of eligibility different from the federal standards. As we observed in King v. Smith, 392 U. S., at 318-319, this rule leaves the States with “considerable latitude in allocating their AFDC resources, since each State is free to set its own standard of need and to determine the level of benefits by the amount of funds it devotes to the program.” The Court today quotes this observation but misses its import. The States have latitude to adjust benefits in the two ways mentioned, but not by imposing additional conditions of eligibility. When across-the-board adjustments like those are made, legislators cannot single out especially unpopular groups for discriminatory treatment.12
For these reasons, I would affirm the judgment of the District Court.
Appellants state that the Work Rules do not “constitute an additional condition of eligibility for public assistance.” Reply Brief for Appellant N. Y. State Depts. 9. The arguments they present, however, relate entirely to the purported congressional authorization for additional conditions of this sort.
The federal conditions of eligibility relating to registration for employment are found in 42 U. S. C. § 602 (a) (19) (1970 ed., Supp. I).
The United States, as amicus curiae, argues that the rule stated in Townsend v. Swank, 404 U. S. 282 (1971), does not fairly characterize the course of our interpretation of the Social Security Act. It relies primarily on the Court’s decision in Wyman v. James, *425400 U. S. 309 (1971). But, for reasons that escaped me at the time, see id., at 345 n. 7, the Court did not address the statutory argument. Wyman does not, therefore, express any limitation on the rule in Townsend. Similarly, our summary affirmance in Snell v. Wyman, 393 U. S. 323 (1969), where the District Court did not have before it our opinion in King v. Smith, 392 U. S. 309 (1968), is at least offset by the summary affirmances in Carleson v. Taylor, 404 U. S. 980 (1971), Juras v. Meyers, 404 U. S. 803 (1971), and Weaver v. Doe, 404 U. S. 987 (1971).
The United States’ argument from authority is weak, and its argument as a matter of logic is even weaker. The United States suggests that, while States may not narrow the class of persons eligible for assistance under federal standards, they may impose additional conditions of eligibility in pursuit of independent state policies. This distinction will not withstand analysis, for it makes decision turn on meaningless verbal tricks. One could just as easily find an independent state policy in Townsend as a narrowing of the class of eligible persons: the State might have a policy of minimizing subsidies to persons with.a clear prospect of future income well above the poverty level, by denying assistance to persons attending four-year colleges while granting it to those attending vocational training schools. Such a system of subsidies would almost certainly be held constitutional under the Due Process Clause, and the position of the United States seems to be that States may impose conditions of eligibility, not squarely in conflict with federal standards, in the pursuit of some constitutional state interest.
For example, no child under 16 or attending school full time need register. 42 U. S. C. § 602 (a) (19) (A) (i) (1970 ed., Supp. I). I take it that the Court would find a conflict “of substance,” ante, at 423 n. 29, between this provision and a state work requirement applicable to children under 16. For the legislative history is clear that Congress, in defining the work-related conditions of eligibility, “spell [ed] out those people we think should not be required to go to *426work,” as Senator Long put it. 113 Cong. Ree. 32593 (1967). See also S. Rep. No. 744, 90th Cong., 1st Sess., 26. The United States’ position would be, I assume, that such a provision would narrow the class of persons eligible for assistance.
Appellants argue that “the provision of section 602 (a) (10) that aid be furnished 'to all eligible individuals’ when read within the context of the Social Security Act means individuals 'eligible’ under State requirements, not Federal.” Reply Brief for Appellant N. Y. State Depts. 13. We expressly rejected this argument in Townsend, 404 U. S., at 286.
The States may, of course, adopt procedures necessary to insure that offers of employment are transmitted to recipients of public assistance. It hardly needs extended argument, however, to show that the New York Work Rules, taken as a whole, are not necessary to do that.
In 1956, Congress required States to adopt plans to provide social services to strengthen family life. Pub. L. 880, §312, 70 Stat. 848.
The original proposal for a Work Incentive Program would have permitted a State to operate Community Work and Training Programs only if a federal WIN Program were not operated in the State. H. R. 5710, 90th Cong., 1st Sess., §204 (a). Thus, either a WIN Program or a state program could operate within a State, but not both. In the final version, the pre-existing authorization for Community Work and Training Programs was eliminated, and the Federal WIN Program was to be implemented in every State. Again, Congress recognized that federal and state work programs could not coexist.
The 1971 Amendments to the WIN Program, Pub. L. 92-223, 85 Stat. 802, further demonstrate Congress’ desire to have federal control of work requirements. Each State must establish a “separate administrative unit” to provide social services only in connection with WIN. 42 U. S. C. § 602 (a) (19) (G) (1970 ed., Supp. I). It would be anomalous for Congress to require the States to devote substantial resources to such a unit in connection with the WIN Program, and yet to permit the States to operate independent work programs using federal funds without providing the special services that Congress thought so important.
It is unnecessary for me to discuss at any length the Court’s analysis of the pre-emption problem. I note, as the Court does, ante, at 411 n. 9, that this case does not present the classic question of pre-emption, that is, does the enactment of a statute by Congress preclude state attempts to regulate the same subject? There is no question that New York may impose whatever work requirements it wishes, consistent only with constitutional limitations, when it gives public assistance solely from state funds. See ante, at 412. The question here relates to the conditions that Congress has placed on state programs supported by federal funds. The distinction is not without importance, for it makes inapposite the strictures in our earlier cases and relied on by the Court, against lightly interfering with state programs. Ante, at 413-414. For we must, of course, be cautious when we prevent a State from regulating in an area where, in the absence of congressional action, it has important interests. Holding that the Federal WIN Program is the exclusive method of imposing work requirements in conjunction with federally funded programs of public assistance would have no such impact; New York would remain free to operate public assistance programs with state funds, with whatever work requirements it chose.
See H. Hart & A. Sacks, The Legal Process 1240 (tent. ed. 1958).
In this connection, I cannot let pass without comment the extraordinary use the Court makes of legislative “history,” in relying on exchanges on the floor of the House and Senate that occurred ajter the decision by the District Court in this case. Ante, at 416-417, n. 19. Although reliance on floor exchanges has been criticized in this Court, Schwegmann Bros. v. Calvert Distillers Corp., 341 U. S. 384, 395-397 (1951) (Jackson, J., concurring), there is some force to the more generally accepted proposition that such exchanges, particularly when sponsors of a bill or committee chairmen are involved, are relevant to a determination of the purpose Congress sought to achieve in enacting the bill. United States v. St. Paul, M. & M. R. Co., 247 U. S. 310, 318 (1918). For legislators know how legislative history is made, and they ought to be aware of the importance of floor exchanges. If they disagree with the interpretation placed on the bill in such exchanges, they may offer amendments or vote against it. Thus, Congress, in enacting a statute, may fairly be taken to have endorsed the interpretations offered in such exchanges. None of this is true of post-enactment floor exchanges, which have no bearing on pending legislation and to which a disinterested legislator might well pay scant attention. If Senator Buckley and Representative Carey wished to have a congressional expression of intent on the issue of pre-emption, they were not barred from introducing legislation.
That the possibility of treatment that is so discriminatory as to be unconstitutional is not insubstantial is shown by the Court’s brief discussion of the jurisdiction of the District Court, ante, at 412 n. 11.