This case involves a challenge to New York State’s elimination of the rights of health care providers to receive reasonable compensation when they treat poor Medicare patients. Plaintiff-appellant New York City Health and Hospitals Corporation is a New York public benefit corporation created by New York State. It is a principal provider of hospital services to the low-income population of the City. Plaintiff-Appellant Medical Society of the State of New York, the largest voluntary association of physicians in New York, is a non-profit corporation organized and existing under the laws of New York State. Plaintiffs-appellants Sidney Finkel, M.D., and John A. Bleski, M.D., are physicians who participate in the Medicare program; many of their patients are eligible under both Medicare and Medicaid. Defendant-appellee Cesar A. Perales is the New York State Commissioner of Social Services. Defendant-appellee Louis W. Sullivan, M.D., is Secretary of the United States Department of Health and Human Services (the Secretary). Perales concurs with the views of Sullivan as set out in his brief.
Appellants appeal from a judgment of the United States District Court for the Southern District of New York, Mary Johnson Lowe, J., dismissing plaintiffs’ complaint challenging a regulation of the New York State Department of Social Services as violative of the Medicare Act, Title XVIII of the Social Security Act, 42 U.S.C. §§ 1395-1395ccc, and the Medicaid Act, Title XIX of the Social Security Act, 42 U.S.C. §§ 1396, et seq. The Medicare program provides funds that help subsidize medical care for the elderly and for certain disabled individuals. The Medicaid program subsidizes medical assistance for the poor.
Appellants claim that the regulation at issue, N.Y.Comp.Codes R. & Regs. tit. 18, § 360.10 (1988),1 which has been approved by the Secretary, violates the Medicare and Medicaid Acts. For the reasons given below, we agree. Accordingly, we reverse *856and remand with directions to grant summary judgment for appellants.
I. Introduction
Before addressing the merits of the controversy before us, it is important that we clarify various terms of the relevant statutes. Under the Medicare Act, the federal government provides people who are 65 years of age‘and older and certain disabled individuals (people who are Medicare-eligible) with an inpatient hospital insurance plan known as "Part A”. 42 U.S.C. §§ 1395c-1395i-4. The Medicare Act also provides that people who are Medicare-eligible may voluntarily obtain supplementary insurance for other medical care, including certain physician services, hospital outpatient services, and other health services generally not covered under Part A. 42 U.S.C. §§ 1395j-1395w-4(j). This coverage is known as “Part B” and is the part of the Medicare statute involved in this appeal. To obtain this coverage, a Medicare-eligible person must pay insurance premiums. Once Part B coverage is obtained, the federal government pays 80% of the “reasonable costs” of outpatient hospital services and 80% of “reasonable charges” for physician services rendered to the insured. Reasonable costs and charges are established pursuant to the Medicare Act and regulations. Medicare patients themselves are responsible for paying the remaining “coinsurance” amount (20% of the reasonable costs of hospital services and 20% of the reasonable charges for physician services) and the annual deductible.
The Medicaid Act, a statute separate from the Medicare Act, provides for a joint federal and state funded system which subsidizes medical care for the needy, regardless of age. If a state decides to participate in Medicaid, it proposes a plan which must be approved by the Secretary as conforming with federal requirements. 42 U.S.C. §§ 1396a(a), 1396a(b). The plan must include, among other things, a schedule of payment rates which the state designates for the various kinds of medical care that a Medicaid patient might seek. Id. If the Secretary approves a state’s plan, then the Federal government will assist the state in its reimbursement program with federal Medicaid funds. Those doctors and hospitals who are willing to treat Medicaid patients must agree to accept the designated Medicaid rate and not ask the patient to pay any money beyond that amount. 42 U.S.C. §§ 1320a-7b(d), formerly 42 U.S.C. § 1396h(d), and 42 C.F.R. § 447.15 (1989). New York State is a participant in the Medicaid program.
Returning to Medicare, the authors of the statute recognized in addressing the needs of Medicare patients that the poor Medicare-eligible (those who are eligible for Medicaid as well) generally would not be able to afford to enroll in the optional Part B Medicare coverage described above, because they would not be able to pay the insurance premiums, the 20% coinsurance and the annual deductible. The Act therefore provides, in 42 U.S.C. § 1395v, as elaborated by 42 C.F.R. § 407.40-407.50 (1990), that a state may agree to pay Part B Medicare insurance premiums on behalf of such poor elderly and disabled — whom we shall call “dual eligibles” or “crossovers”— and thereby acquire Part B Medicare coverage for them. By so doing, a state enrolls these crossovers in the Medicare Part B program just as less needy individuals enroll themselves when they individually choose to obtain Part B Medicare coverage and pay the insurance premiums. The federal government contributes funds to subsidize these state “buy-in” arrangements. New York has such a buy-in agreement with the Secretary.
Until 1987, New York paid not only the premiums but also the full cost-sharing amounts — the annual deductible and the 20% of reasonable costs or charges beyond what Medicare covers — for buy-in crossovers. Effective January 1,1987, however, New York changed its practice by enacting the Regulation at issue in this case. The Regulation provided that in the case of crossovers covered by Part B through a buy-in agreement, New York will not pay any cost-sharing amounts except under one set of circumstances: When the 80% of reasonable costs or charges that Medicare reimburses amounts to less than the *857Medicaid rate, New York will pay the difference (Medicaid rate minus 80% reasonable costs or charges). A letter sent by New York State to health care providers illustrates the way that the Regulation operates:
Example: Medicaid Fee or Rate = $45.00
Medicare [80%] Balance
Approved Medicare Paid Due
$80.00 $63.00 $0.00
A claim should not be submitted to Medicaid in this example.
Example: Medicaid Fee or Rate = $50.00
Medicare [80%] Balance
Approved Medicare Paid Due
$60.00 $48.00 $2.00
A claim should be submitted to Medicaid for the amount of $2.00.
The Regulation also prohibits Medicare providers from collecting any money from buy-in dual eligibles themselves.
One effect of the Regulation is that in New York State a dual eligible’s providers may almost never collect more than 80% of their reasonable costs or charges, because the scheduled Medicaid payments are almost invariably less than 80% of the corresponding reasonable costs or charges of a given type of care under Medicare.2 The Regulation has been modified to extend to a group of Medicare-eligible patients who are not poor enough to qualify for Medicaid but have incomes at or below the poverty line. This group is referred to as “qualified Medicare beneficiaries” (QMBs). 42 U.S.C. §§ 1396d(p)(l), 1396d(p)(2)(A). The QMBs may, like dual eligibles, be provided with Part B coverage through a buy-in agreement. 42 U.S.C. § 1396d(p)(3). The modified New York regulation limits New York’s contribution to QMBs’ cost-sharing coverage in the same way it does that of dual eligibles, on the basis of Medicaid rates.
II. Procedural History
This appeal arises out of a challenge to the Regulation as violative of the Medicare and Medicaid Acts. The Regulation has been approved by the Secretary. The approval was apparently not accompanied by an opinion or statement of reasons, and, we are told, was issued after commencement of this litigation. As indicated above, the Regulation became effective January 1, 1987. In the district court, plaintiffs and defendants both moved for summary judgment and defendants also moved to dismiss. While these motions were pending, Congress amended portions of the Social Security Act relevant to the action, and the parties addressed the effect of the amendments in letters to the district court. In an opinion and order dated March 18,1991, the district court denied plaintiffs’ motion and granted defendants’ motions for dismissal of the complaint. The court reasoned that the Secretary’s approval of the Regulation was based upon a permissible construction of the statute and that his interpretation was therefore entitled to deference. Thereafter, judgment was entered but subsequently vacated to permit plaintiffs to file an amended complaint, which included a new count based on amendments to the Medicaid Act that took effect in 1989. In April 1991, the district court entered a final judgment dismissing the amended complaint. This appeal followed.
III. Discussion
In this action, we must determine what New York State’s responsibility is under *858the Medicare and Medicaid Acts for the annual deductible and 20% of reasonable costs or charges for patients who are dual eligibles or QMBs.
Appellants claim that the Regulation violates the Medicare and Medicaid Acts and that the Secretary’s approval of the Regulation is unjustified. Appellees submit that under Chevron U.S.A., Inc. v. Natural Resources Defense Council, Inc., 467 U.S. 837, 844, 104 S.Ct. 2778, 2782, 81 L.Ed.2d 694 (1984), we are required to defer to the Secretary’s interpretation of the statute at issue unless the interpretation is “manifestly contrary” to the statute. Although we recognize, as did the district court, that the Medicare and Medicaid Acts are very complicated, this is one of those comparatively rare instances when we should not defer to an administrator’s interpretation of a statute. First, as we explain below, the Regulation is at odds with the clear intent of the statutes, both facially and as elaborated by legislative history. See Chevron, 467 U.S. at 842-43, 104 S.Ct. at 2781-82. Second, the Secretary’s policy has been inconsistent with respect to the particular question at issue, and his current position is therefore entitled to less deference.
Medicare Act
Under the Medicare Act, a provider of services to a Medicare-eligible individual pursuant to the Medicare Act receives from the federal government, after deduction of the annual deductible, 80% of the reasonable costs or charges for such services. To collect the remaining portion of the provider’s compensation, the provider “may charge such [Medicare-eligible] individual or other person (i) the amount of any deduction ... and (ii) an amount equal to 20 per centum of the reasonable charges for such items and services ... for which payment is made under part B .... ” 42 U.S.C. § 1395cc(a)(2)(A). In other words, providers who furnish medical care to Medicare-eligible patients have the right to collect 100% of their reasonable costs or charges. Mercy Community Hosp. v. Heckler, 781 F.2d 1552, 1556-57 (11th Cir. 1986); St. James Hosp. v. Heckler, 760 F.2d 1460, 1472 (7th Cir.1985), cert. denied, 474 U.S. 902, 106 S.Ct. 229, 88 L.Ed.2d 228 (1985); Menorah Medical Center v. Heckler, 768 F.2d 292, 296 (8th Cir.1985); Regents of Univ. of Cal. v. Heckler, 771 F.2d 1182, 1188-89 (9th Cir.1985). As appellants note, there is nowhere articulated in the Medicare Act or regulations an exception for dual eligibles or QMBs or any limitation on providers’ express statutory right to recover their full reasonable costs or charges. Despite this right, the Regulation at issue limits New York State’s cost-sharing contribution to the Medicaid rate, an amount that is less than a provider’s reasonable costs or charges, and prohibits providers from collecting anything from the patients themselves. In other words, the Regulation precludes providers who serve dual eligibles and QMBs pursuant to a buy-in arrangement from collecting more than 80% of their reasonable costs or charges in the overwhelming majority of cases.
The Regulation therefore appears, on its face, to violate the Medicare Act. The Secretary has nevertheless approved it, on the ground, accepted by the district court, that dual eligibles and QMBs are “primarily Medicaid patients” since they receive Part B Medicare coverage only because the State has enrolled them due to their status as Medicaid patients or poor individuals. In the Secretary’s understanding, then, providers supplying care to such individuals are therefore not entitled to receive their reasonable costs or charges. We do not accept this reasoning. The Medicare Act on its face entitles providers to collect their reasonable costs or charges, an entitlement which is frustrated by the Regulation.
The Secretary’s interpretation of dual eli-gibles as primarily Medicaid patients leads to some oddities. If Medicaid alone controlled with respect to dual eligibles, then it would make little sense for Medicare Part B to pay 80% of the Medicare rate for crossover care. If Medicaid were in fact the controlling program, then one would expect providers to be compensated at the Medicaid rate, instead of at 80% of the Medicare rate. Moreover, if crossovers *859were “primarily Medicaid patients,” there would be no basis for Medicare to allow (as it does), as a hospital’s bad debt expense, the uncollected Medicare cost-sharing amounts.
Beyond the face of the statute, the Senate Report accompanying the initial Medicare Act reveals that Congress sought to avoid a wealth-based, two-tiered system of health care for the elderly and certain disabled and indeed wanted to integrate all of those who were Medicare-eligible into the existing health care system. “Since the reasonable cost of the services would be covered, hospitals would not be deterred, because of nonpaying or underpaying patients in this aged group, from trying to provide the best of modern care.” S.Rep. No. 404, 89th Cong., 1st Sess. 27 (1965), reprinted in 1965 U.S.C.C.A.N. 1943, 1967-68. “The provision of insurance against the covered costs would encourage participating institutions, agencies, and individuals to make the best of modern medicine more readily available to the aged.” S.Rep. No. 404, 89th Cong., 1st Sess. at 24, 1965 U.S.C.C.A.N. at 1965.
Deeming dual eligibles and QMBs to be primarily Medicaid rather than Medicare patients prevents health care providers from collecting their reasonable costs or charges. Providers will consequently refrain from treating the most vulnerable of the elderly and disabled, those who are also poor. These groups are the true subjects of this appeal, and such a result is fundamentally at odds with Congress’ vision in enacting the Medicare Act.
The buy-in provisions of Medicaid
The statutory section that specifies cost-sharing obligations for buy-ins is 42 U.S.C. § 1396a(a). It mandates that “[a] State plan for medical assistance [Medicaid] must _ provide,” id. at § 1396a(a)(10), “for making medical assistance [Medicaid] available for medicare cost-sharing (as defined in section 1396d(p)(3) of this title) for qualified medicare beneficiaries described in section 1396d(p)(l) _” Id. at § 1396a(a)(10)(E). Cost-sharing is defined as Part B premiums, deductibles and the difference between the amount paid by Medicare (80%) and “the amount that would be paid under such section if any reference to ‘80 percent’ therein were deemed a reference to ‘100 percent’ [i.e., 20%].” 42 U.S.C. § 1396d(p)(3). The apparent meaning of this section is that the states that participate in Medicaid must allocate Medicaid funds to the enrollment of all dual eligibles and QMBs in Part B of Medicare and to the payment of 20% of reasonable costs or charges along with the annual deductibles incurred in this program.
Appellees claim that 42 U.S.C. § 1396a(a)(10)(E), quoted above, requires only that a state make Medicaid funds available (to pay cost-sharing amounts for buy-ins) up to the Medicaid rates. Appel-lees base this claim in part on Congress’ simultaneous enactment in 1986 of § 1396a(a)(10)(E) and 42 U.S.C. § 1396a(n). The latter provision permits state reimbursement of cost-sharing amounts to QMBs to exceed the Medicaid rates. According to appellees, Congress would not simultaneously require (under (a)(10)(E)) and permit (under a(n)) the same result.
Although the argument has a surface appeal, upon analysis it is not persuasive. A statute requiring Medicaid funds to be made available for Medicare cost-sharing can only sensibly be read as requiring the funds to be made available to cover all Medicare cost-sharing. It is counter-intuitive that a statute requiring Medicaid funds to be made available for cost-sharing only to the extent of the Medicaid scheduled rates would not specify that qualification expressly. Furthermore, it appears that the reason that section a(n) authorizes payment beyond the Medicaid amount, when it is required by another section, is to clarify that the Medicaid Act3 does not prohibit a provider from accepting more than the Medicaid rate. To ensure that it be understood that providers of care to dual eligi-*860bles and QMBs are allowed and entitled to accept the state’s full cost-sharing reimbursement, which (a)(10)(E) now mandates, a(n) gives providers this explicit authorization. As we hold today, a Medicare provider need not be satisfied with inadequate payment, i.e., less than reasonable costs or charges, even when that provider is treating a Medicare patient who happens also to be poor.
Predecessor to § 1396a(a)(10)(E)
To support their position that the Regulation is not contrary to the Medicare and Medicaid Acts, appellees rely on, among other things: a predecessor section to (a)(10)(E); a district court decision construing that earlier section; and legislative history. Before 42 U.S.C. § 1396a(a)(10)(E) was enacted, 42 U.S.C. § 1396a(a)(15) of the Medicaid Act governed a state’s obligations to pay cost-sharing amounts for patients enrolled in Part B of Medicare under a buy-in arrangement. Although (a)(15) has been repealed, effective July 1, 1989, both parties in this case discuss it extensively. The district court’s original judgment was addressed to the Secretary’s interpretation of (a)(15) but this earlier judgment was vacated and the court later took into account the new (a)(10)(E) in rendering its final judgment. We shall analyze section (a)(15) for the guidance it provides in understanding the section that replaced it.
Prior to its repeal, (a)(15) required that a state Medicaid plan “provide where, under the plan, all of any deductible, cost sharing, or similar charge imposed with respect to such individual [covered by Part B under a buy-in arrangement] ... is not met, the portion thereof which is met shall be determined on a basis reasonably related ... to such individual’s income or his income and resources[.]” We understand this section to mean that if the state chooses not to pay the entire cost-sharing amount, the state must pay what remains after patients are allocated that portion of the liability commensurate with their ability to pay. Appel-lees claim that this section is only a limitation on how much a patient may be charged but not an indication of the minimum required of a state. We disagree. If the only purpose of the section were to put a ceiling on what a buy-in patient could be charged, the section could have stated as much. The significance of the statute as written is to provide two alternatives: either a state pays all cost-sharing amounts, or the state pays all except that portion allocated to the patient based on the patient’s income and resources.
This understanding is also consistent with the providers’ entitlement under Medicare to receive 100% of their reasonable costs or charges. Whether the state pays these costs or charges in full or whether part is allocated to the patient based on ability to pay, the provider is compensated and is therefore encouraged to continue to treat the poor elderly and disabled. This encouragement serves the goals of the Medicare Act. To the extent that (a)(15) guides our reading of successor section (a)(10)(E), the meaning of (a)(15) is consistent with a requirement for payment of all cost-sharing amounts by the state under (a)(10)(E). At most, (a)(15) might support an argument that (a)(10)(E) incorporated the alternative of allocating a portion of liability to patients based on their ability to pay.
Appellees also rely on Samuel v. California Dep’t of Health Services, 570 F.Supp. 566 (N.D.Cal.1983), to support the validity of the Regulation, at least under the former section (a)(15). In Samuel, a California district court upheld a state regulation which, like the Regulation here, limited the state’s obligation to pay cost-sharing reimbursement for buy-in dual eligibles on the basis of the state’s Medicaid rates. Id. at 574. The court also held that providers may not collect these amounts directly from dual eligibles, under what was formerly Medicaid, 42 U.S.C. § 1396h(d)(l) but has now been recodified as 42 U.S.C. §§ 1320a-7b(d). Id. Appellees assert that, as the court noted in Samuel, there was no clear intent in the legislative history of (a)(15) to protect providers by guaranteeing them reimbursement. 570 F.Supp. at 570. We disagree. Moreover, we would include in any examination of legislative history an examination of the history of the Medicare *861Act, since those individuals covered by Part B under (a)(15) are Medicare patients. As we have already indicated, the Senate Report accompanying the Medicare Act evidenced an intent to provide quality medical care for the elderly by compensating providers reasonably for their care. A guarantee of reimbursement, by protecting providers, protects patients.
Finally, appellees suggest that the “subsequent legislative history” of (a)(15) reveals that (a)(15) permitted the limitation of a state’s cost-sharing obligations for dual eligibles on the basis of Medicaid rates. Appellees cite, for example, the House Report on the Medicare Catastrophic Coverage Act of 1988, which noted that “with respect to dual Medicaid-Medicare eligi-bles, some states pay the coinsurance even if the amount that Medicare pays for the service is higher than the State Medicaid payment rate, while others do not.... [I]f a State chooses to pay some or all of the coinsurance in this circumstance [where the Medicaid rate is lower than what Medicare covers], Federal matching funds would, as under current law, be available for this cost.” H.R.Rep. No. 105(11), 100th Cong., 2d Sess. 61 (1988), reprinted in 1988 U.S.C.C.A.N. 803, 857, 884. Appellees also cite the legislative history of the Omnibus Budget Reconciliation Act of 1989, in which Congress recognized that most states limit reimbursement for dual eligibles to the Medicaid rate. H.R.Rep. No. 247, 101st Cong., 1st Sess. 364 (1989), reprinted in 1989 U.S.C.C.A.N. 1906, 2089-90.
As appellants rightly contend, the Committee reports cited, written more than 20 years after enactment of the Medicare and Medicaid Acts, do not mention or purport to construe (a)(15). They merely refer to what the Committee understood to be the practice of some states concerning payment of cost-sharing amounts. Furthermore, even when a subsequent House Committee has actually commented upon an earlier statute, the interpretation carries little weight with the courts. See Oscar Mayer & Co. v. Evans, 441 U.S. 750, 758, 99 S.Ct. 2066, 2072, 60 L.Ed.2d 609 (1979); Pierce v. Underwood, 487 U.S. 552, 566, 108 S.Ct. 2541, 2550, 101 L.Ed.2d 490 (1988); United States v. Price, 361 U.S. 304, 313, 80 S.Ct. 326, 332, 4 L.Ed.2d 334 (1960). We accordingly refuse to read the subsequent legislative history which appellant cites as evidence that the Regulation is valid, under either the former (a)(15) or the current (a)(10)(E).
Inconsistency of the Secretary’s policy
As we stated above, where — as here — an issue is a question of law involving statutory construction and analysis of Congressional intent, and the meaning of the statute is clear, an agency interpretation is entitled to less deference. INS v. Cardoza-Fonseca, 480 U.S. 421, 446-48, 107 S.Ct. 1207, 1221, 94 L.Ed.2d 434 (1987); Chevron, 467 U.S. at 843 n. 9, 104 S.Ct. at 2781 n. 9; International Union, United Automobile, Aerospace and Agricultural Implement Workers of America v. Brock, 816 F.2d 761, 764 (D.C.Cir.1987). But even where a statute is ambiguous or silent on a particular question — as we do not believe the Medicare and Medicaid statutes are with respect to the question before us— where the Secretary’s policy is inconsistent with an earlier policy, that inconsistency is a ground for rejecting a claim for deference. In Cardoza-Fonseca, for example, the Supreme Court stated that “[a]n agency interpretation of a relevant provision which conflicts with the agency’s earlier interpretation is ‘entitled to considerably less deference’ than a consistently held agency view.” 480 U.S. at 446 n. 30, 107 S.Ct. at 1221 n. 30 (citations omitted). In Samaritan Health Service v. Bowen, the Court of Appeals for the D.C. Circuit struck down as unreasonable the Secretary’s interpretation of a provision of Medicare, an interpretation that had led to the denial of Medicare reimbursement claims. The court stated in its opinion that “[a]ny deference that an interpretive rule may claim depends on [among other things] ... ‘its consistency with earlier and later pronouncements _’” 811 F.2d 1524, 1529 (D.C.Cir.1987), citing Skidmore v. Swift & Co., 323 U.S. 134, 140, 65 S.Ct. 161, 164, 89 L.Ed. 124 (1944). The expertise in statutory interpretation to which we normally *862defer becomes dubious when the expert cannot make up its own mind.
This case presents an example of such inconsistency. Although appellees assert that the Secretary’s approval of the Regulation accords with his longstanding policy, this assertion is not entirely accurate. In a 1981 policy memorandum, the Secretary announced that with respect to dual eligibles who have buy-in Medicare coverage, “if the MediCal [Medicaid] agency has made no payment at all, the physician/supplier may collect coinsurance [i.e. 20% of reasonable charges] and deductibles from the MediCal [Medicaid] eligible patient.” Department of Health & Human Services Memorandum, September 29, 1981 (emphasis added). As we stated above, under the New York Regulation, the providers for most dual eligibles and QMBs who have buy-in Part B coverage will receive nothing from Medicaid because the 80% which Medicare pays will exceed the Medicaid rate. Therefore, the providers for these buy-in patients would have been authorized, under the Secretary’s 1981 policy, to collect coinsurance from their patients directly. In Samuel, the California district court case we discussed above, the Secretary urged this position with the State of California:
Suppose, however, the doctor chooses not to bill MediCal [Medicaid] but only Medicare. In that case the doctor, depending on his conscience, may take his 80% reimbursement from Medicare and bill the beneficiary the remaining 20%. Note that this is totally outside the State plan and beyond the reach of any proscriptions which might be imposed under the Medicaid Act; whether the doctor bills the patient in the Medicare-only situation is a matter between the doctor and his patient. The State cannot control physicians and cannot stop them from billing certain charges permitted by the federal government, (emphasis added)
Similarly, the Secretary there asserted:
What the plaintiffs are really complaining about is the practice of some doctors in charging co-payments to their patients. Congress has seen fit to allow the doctors discretion to impose such charges and if plaintiffs are unhappy about it their remedy is to seek corrective legislation, (emphasis added)
Thus, in 1981 the Secretary presumed that providers have the right to receive 100% of their reasonable costs or charges for services to patients enrolled in Part B Medicare pursuant to a buy-in arrangement, a right that providers could assert even against indigent, Medicaid-eligible patients. The Secretary did not consider such patients to be “primarily Medicaid” in 1981. We reject the Secretary’s reading of the statutes to suggest that these patients are “primarily Medicaid” in 1991.4
IV. Conclusion
When faced with a complicated statutory scheme, there is a strong temptation for judges to assume that the scheme has no fixed meaning or purpose and simply to defer to the interpretation given the statutory text by an administrative agency. In a society as complex as ours, many statutes are of necessity complicated. However, complexity is not the same as ambiguity. Congress passes legislation with specific purposes in mind. When the ordinary tools of statutory construction permit us to do so, we must attempt to discover those purposes from the text, structure and *863history of the acts in question. Sometimes we will find that Congress has not addressed the problem posed by a particular case. In such circumstances, we are required to defer to administrative expertise. But where we confront a statute that evinces a legislative purpose clearly at odds with the proffered administrative interpretation, we should not defer. Indeed, our constitutional duty to interpret the law requires us to effectuate the legislative intent notwithstanding the contrary administrative view.
We have considered all of appellees’ arguments and, for the reasons set forth above, we reverse the judgment of the district court and remand with directions to grant summary judgment to appellants.
. Effective March 1, 1989, 18 NYCRR § 360.10 was repealed and recodified as 18 NYCRR § 360-7.7. For purposes of consistency, the regulation will be referred to as "the Regulation.”
. Because the record reflects that this conclusion is true and appellees do not dispute it, we shall assume that it is true and that New York in most cases now pays no part of Part B cost-sharing amounts. •
. Specifically, 42 U.S.C. §§ 1320a-7b(d), formerly § 1396h(d), as elaborated by 42 C.F.R. § 447.15 (1989).
. It is true that in Chevron, the Federal Agency at issue — the E.P.A. — had adopted different policies with respect to the definition of “stationary source” under the Clean Air Act from one administration to the next. See Chevron, 467 U.S. at 863-64, 104 S.Ct. at 2792. However, these policies were both within the policy-making authority implicitly delegated by Congress to the agency in flexibly implementing its statute. In our case, by contrast, the position that Medicare providers are entitled to collect their fees from dual eligibles (the Secretary's position in 1981) is absolutely at odds with the position that the providers are bound to accept only the Medicaid scheduled amount for dual eligibles (the Secretary’s position in 1991). Congress intended either that buy-in patients be responsible for cost-sharing or that they not be responsible for cost-sharing. The Secretary changed policies not because he found that one of two permissible policies was more desirable in implementing the unspoken intent of Congress. The Secretary changed because, as he submits in his brief, he now believes that the previous policy was in error.