At issue in this case is whether Plaintiff-appellee Donald Dean Walker’s (Debtor) individual retirement annuities (IRA’s) and Keogh annuities should be included as property of his bankruptcy estate, and, if included, whether the annuities are subject to exemption from the estate pursuant to the relevant Oklahoma exemption statutes. 1 Under the Bankruptcy Code, virtually all property in which a debtor has a legal or equitable interest at the commencement of the case is included in the bankruptcy estate, see 11 U.S.C. § 541, but a debtor may exempt certain property from the estate, see id. § 522. The Code includes a list of properties which may be exempted, see id. § 522(d), and it allows states to establish separate exemption lists. A debtor may choose either the federal exemption provisions or the state provisions unless he resides in a state that has *896 “opted out” of the federal exemption list. See id. § 522(b)(1); 3 Collier on Bankruptcy-11 522.02, (15th ed. 1991). In states that have “opted out,” debtors are limited to the state exemption list. The relevant state in this case, Oklahoma, has “opted out.” See- Okla.Stat.Ann. tit. 31, § IB (West 1991). Oklahoma bankrupt debtors therefore are limited to the Oklahoma exemptions. See id. § 1A (exemptions).
Debtor filed for Chapter 7 bankruptcy protection and claimed two IRA’s and a Keogh as exempt from the bankruptcy estate pursuant to Okla.Stat.Ann. tit. 31, § 1A(20). The Oklahoma statute allows debtors to exempt both IRA’s and Keoghs provided the investments fully qualify for tax deferral treatment under the Internal Revenue Code.
Id.
The Defendant-appellant Trustee challenged the exemptions, contending that the Oklahoma statute was invalid. In a core proceeding resulting in a published final order, the bankruptcy court ruled in favor of Trustee.
See In re Walker,
Trustee appeals from the district court judgment. He contends that the Oklahoma exemption statute is invalid because (1) it is an unconstitutional impairment of contracts, (2) it is preempted by the Employee Retirement Income Security Act of 1974 (ERISA), and (3) it exceeds the scope of authority delegated to the States pursuant to § 522 of the Bankruptcy Code to establish bankruptcy exemptions. In the alternative, Trustee argues that Debtor did not meet his burden of proving that the annuities in question were not overfunded and therefore fully tax exempt. The Trustee did not raise this alternative argument below, and he has not attempted to articulate a reason for us to depart from the general rule that “a federal appellate court does not consider an issue not passed upon below.”
Singleton v. Wulff,
I. The Annuities.
The bankruptcy court made specific findings regarding the annuities in this case.
See
II. Bankruptcy Estate Property.
Before reaching the Oklahoma exemption issues, we must determine whether the annuities in this case should be included in the bankruptcy estate pursuant to 11 U.S.C. § 541. As stated above, § 541 en *897 compasses virtually all property in which a debtor has a legal or equitable interest as of the time of the bankruptcy petition. Even properties with underlying agreements which contain restrictions on transfer are included. See id. § 541(c)(1)(A). Nevertheless, § 541 contains an exception for “a restriction on the transfer of a beneficial interest of the debtor in a trust that is enforceable under applicable nonbank-ruptcy law-” Id. § 541(c)(2). 3 Such anti-alienability provisions remain enforceable under the statute; therefore, a debt- or’s interest in the trusts does not enter the bankruptcy estate.
The circuits are split over the scope of § 541(c)(2)’s exception for anti-alienability provisions that are enforceable under “applicable nonbankruptcy law.” Four circuits have held that the provision refers exclusively to state spendthrift trust law.
See Daniel v. Security Pacific National Bank (In re Daniel),
Debtor seizes on the § 541(c)(2) exception as an alternative ground for affirmance, contending that his annuities should be excluded from the bankruptcy estate because they are enforceable spendthrift trusts under Oklahoma law.
See
Okla. Stat.Ann. tit. 60, § 175.25 (West 1971). In support of this proposition, he cites
Greening Donald Co. v. Oklahoma Wire Rope Products, Inc.,
Greening Donald
turned on the court’s interpretation of Okla.Stat.Ann. tit. 60, §§ 326-28 (West 1971), which provides that retirement trusts are exempt from state garnishment proceedings provided they meet certain criteria.
4
Specifically, the
*898
court applied the statute to an Individual Retirement Account, holding that the Account was exempt from garnishment because it qualified for tax deferral treatment under the Internal Revenue Code and contained an anti-alienability clause.
See Greening Donald,
III. Exempt Property.
Debtor’s IRA’s and Keogh undisputedly fit within the Oklahoma exemption statute. See Okla.Stat.Ann. tit. 31, § 1A(20) (West 1991). 5 Therefore, barring some legal deficiency in the application of or on the face of the statute, the IRA’s and Keoghs should be exempted from the bankruptcy estate pursuant to 11 U.S.C. § 522. Trustee urges us to reinstate the bankruptcy court’s holding that the Oklahoma exemption statute as applied is unconstitutional because it impairs the creditors’ ability to collect on their contracts, all of which were entered before the effective date of the *899 statute. See U.S. Const. Art. I, § 10, cl. 4, (“No State shall ... pass any ... Law impairing the Obligation of Con-tracts_”).
Recognizing that the Contracts Clause “prohibition must be accommodated to the inherent police power of the State ‘to safeguard the vital interests of its people,’ ” the Supreme Court has crafted a three-part test to determine whether retroactive state legislation that affects contracts is unconstitutional.
See Energy Reserves Group, Inc. v. Kansas Power & Light Co.,
We need not address whether the Oklahoma statute represents a “substantial impairment,” for we are confident that any such impairment is a justifiable exercise of Oklahoma’s inherent police power. The district court correctly identified a “significant and legitimate” public purpose — the provision for bankrupt debtor families’ needs.
See In re Walker,
Here is no example of legislation at its fairest; here is no sign of intensive study of the consequences of what has been done, nor safeguarding the future on the basis of responsible forecasts.... Here is a sweeping, heedless delegation, to a foreign Congress occupied with different concerns, of unqualified power to destroy a venerable and well-founded tradition guarding against abuse of spendthrift trusts, the practical consequence being that the Uhited States Congress, in tinkering with its own tax laws, unknowingly grants a license to defraud creditors to citizens of the State of Oklahoma. These are not reasonable conditions, of a character appropriate to a legitimate purpose. ...
In re Garrison,
The bankruptcy court’s concern for the thoughtless “tinkering” of a “foreign Congress” seems peculiar when considering that Oklahoma’s authority to legislate bankruptcy exemptions flows from that very congress.
See
11 U.S.C. § 522(b)(1). Even so, the court correctly asserted that the Oklahoma exemption statute may not be an “example of legislation at its fairest,” but “legislation at its fairest” is not a realistic goal. Legislatures must balance competing interests before passing any statute, and it is not our function as federal courts to second guess the resulting choice. On the contrary, “[u]nless the State itself is a contracting party, ... ‘[a]s is customary in reviewing economic and social regulation, ... courts properly defer to legislative judgment as to the necessity and reasonableness of a particular measure.”
Energy Reserves,
*900
Affording appropriate deference to the policy choice of the Oklahoma legislature, we agree with the district court that no reason exists to declare the exemption statute an unconstitutional impairment of contract. The bankruptcy court focused on the bank-account-like quality of some qualifying IRA’s, stating that a debtor can use the accounts “as he pleases but creditors cannot reach [the accounts] at all.”
In re Garrison,
Trustee next argues that ERISA preempts the exemption statute even though Debtor’s annuities are not subject to ERISA regulation. This supposedly is because the non-ERISA portion of the exemption statute is not severable under state law from the “[unquestionably” preempted ERISA portion pursuant to the Supreme Court’s holding in
Mackey v. Lanier Collection Agency & Service, Inc.,
We will not decide the ERISA preemption issue until it is squarely before us. Without the benefit of briefing from parties who are litigating ERISA plan exemptions, it would be inappropriate in this case for us to declare unconstitutional the ERISA portion of the statute, and then extend that holding via a severability analysis to the relevant portion of the statute. In any event, the ERISA portion of the Oklahoma exemption statute is superfluous in the bankruptcy context — we have already held that ERISA plans may be excluded altogether from the estate pursuant to 11 U.S.C. § 541(c)(2).
6
See In re Harline,
Trustee’s final argument is equally meritless. Pursuant to Congress’ authority to establish uniform bankruptcy laws,
see
U.S. Const, art. I, § 8, cl. 4, it may delegate to the States the authority to legislate bankruptcy exemptions.
See Stellwagen v. Clum,
We AFFIRM the district court judgment and remand for further proceedings consistent with this opinion.
Notes
. Individual Retirement Annuities are self-settled trusts that qualify for tax deferral treatment under I.R.C. § 408(b). “Keoghs,” trusts for self-employed individuals, qualify for tax deferral treatment under I.R.C. § 401(c), (d) and miscellaneous other Code provisions. See Keogh-Smathers Act, Pub.L. No. 87-792, 76 Stat. 809 (1962).
. The bankruptcy court found that Debtor’s annuities were “non-ERISA-qualified” plans.
. The statute provides in relevant part:
(c)(1) Except as provided in paragraph (2) of this subsection, an interest of the debtor in property becomes property of the estate under subsection (a)(1), (a)(2), or (a)(5) of this section notwithstanding any provision in an agreement, transfer instrument, or applicable nonbankruptcy law—
(A) that restricts or conditions transfer of such interest by the debtor; or
(B) that is conditioned on the insolvency or financial condition of the debtor, on the commencement of a case under this title, or on the appointment of or taking possession by a trustee in a case under this title or a custodian before such commencement, and that effects or gives an option to effect a forfeiture, modification, or termination of the debtor’s interest in property.
(c)(2) A restriction on the transfer of a beneficial interest of the debtor in a trust that is enforceable under applicable nonbankruptcy law is enforceable in a case under this title.
11 U.S.C. § 541(c) (emphasis supplied).
. The statute provides in relevant part:
RETIREMENT, PENSION OR PROFIT SHARING PLAN
§ 326. Perpetuities and restraints on alienation.
No retirement, pension or profit sharing plan, qualified for tax exemption purposes under present or future Acts of Congress, or any trusts, insurance and annuity contracts constituting a part thereof, shall be construed as violating the rule or law against perpetuities, or any rule or law against restraints on alienation; provided....
*898 § 327. Provisions against alienation or encumbrance.
Any such plan, trust or contract may provide against the alienation or encumbrance of the interest of any person therein and further provide that no interest therein shall be subject to garnishment, attachment, execution or the claims of creditors of the persons having an interest therein.
§ 328. Power to alienate or encumber — Exemption from process and claims
Any person having an interest in any such plan, trust or contract, or in any property or any right subject to any such plan, trust or contract, containing the provisions set forth in [§ 327], or provisions of substantially the same force and effect, shall have no right to alienate or encumber such right or interest in any manner contrary thereto, and the interest of any such person in any such plan, trust or contract, or in any property or any right subject to any such plan, trust or contract, shall be exempt from garnishment, attachment, execution or the claims of creditors.
Okla.Stat.Ann. tit. 60 (West 1971).
. The statute provides in relevant part:
§ 1. Property exempt from attachment, execution or other forced sale — Bankruptcy proceedings
A. ... the following property shall be reserved to every person residing in the state, exempt from attachment or execution and every other species of forced sale for the payment of debts, except as herein provided:
20. Subject to the Uniform Fraudulent Transfer Act, Section 112 et seq. of Title 24 of the Oklahoma Statutes, any interest in a retirement plan or arrangement qualified for tax exemption purposes under present or future Acts of Congress; provided, such interest shall be exempt only to the extent that contributions by or on behalf of a participant were not subject to federal income taxation to such participant at the time of such contributions, plus earnings and other additions thereon; provided further, any transfer or rollover contribution between retirement plans or arrangements which avoids current federal income taxation shall not be deemed a transfer which is fraudulent as to a creditor under the Uniform Fraudulent Transfer Act. "Retirement plan or arrangement qualified for tax exemption purposes" shall include without limitation, trusts, custodial accounts, insurance, annuity contracts and other properties and rights constituting a part thereof. By way of example and not by limitation, retirement plans or arrangements qualified for tax exemption purposes permitted under present Acts of Congress include defined contribution plans and defined benefit plans as defined under the Internal Revenue Code ("IRC”), individual retirement accounts, individual retirement annuities, simplified employee pension plans, Keogh plans, IRC Section 403(a) annuity plans, IRC Section 403(b) annuities, and eligible state deferred compensation plans governed under IRC Section 457. This provision shall be in addition to and not a limitation of any other provision of the Oklahoma Statutes which grants an exemption from attachment or execution and every other species of forced sale for the payments of debts. This provision shall be effective for retirement plans and arrangements in existence on, or created after the effective date of this act....
Okla.Stat.Ann. tit. 31 (West 1991).
. Even if we were to hold unconstitutional the ERISA portion of the statute, we would agree with the Debtor that the non-ERISA portion of the statute is severable. Severability is a question of state law,
Watson v. Buck,
