MEMORANDUM FINDINGS OF FACT AND OPINION

THORNTON, Judge: Respondent determined a $ 1,114,795 Federal estate tax deficiency with respect to the Estate of Rose B. Posner (the estate). The parties have resolved all issues raised in the notice of deficiency. The estate contends, however, that it is entitled to a $ 2,909,000 estate tax refund because certain marital trust property was erroneously included in the gross estate. Resolution of this issue turns upon these two subissues: (1) Whether Rose B. Posner (decedent) possessed a general power of appointment over the marital trust property in question under section 2041; and (2) whether the duty of consistency requires the estate to treat decedent as possessing a general power of appointment under section 2041. ¹ Finally, if we determine that the estate is entitled to a refund of an estate tax overpayment, we must decide whether this Court has jurisdiction at this juncture to award interest on the overpayment.

2004 Tax Ct. Memo LEXIS 112">*113              FINDINGS OF FACT

The parties have stipulated most of the facts, which we incorporate along with the associated exhibits into our findings of fact. On October 28, 1996, decedent died in Baltimore County, Maryland. When the petition was filed, David B. Posner (David), the personal representative of the estate, resided in Reisterstown, Maryland.

Mr. Posner's Will

Decedent was formerly married to Nathan Posner (Mr. Posner). On April 21, 1975, Mr. Posner died. He was survived by decedent and their three children, David, Judith Geduldig, and Carol Jean Posner Gordon.

Mr. Posner's will devised half of his estate to a marital trust (the marital trust) for decedent's benefit. Item II of Mr. Posner's will created the marital trust, and item XIV set forth provisions for its administration. Specifically, item II of Mr. Posner's will provided:

     If my wife, Rose B. Posner, shall survive me, I give,

   devise and bequeath to my Trustees, hereinafter named, in trust

   and confidence, nevertheless, for the uses and purposes

   hereinafter set forth, an amount equal to one-half (

Item XIV of Mr. Posner's will provided:

2004 Tax Ct. Memo LEXIS 112">*114      Anything in this Will to the contrary notwithstanding, and

   whether or not any reference is made in any other provision of

   this Will to the limitations imposed by this Section XIV, my

   Trustee shall not have or exercise any authority, power or

   discretion over the Marital Trust or the income thereof, or the

   property constituting the same, nor shall any payment or

   distribution by my Trustee be limited or restricted by any

   provision of this Will, which would in any way (a) adversely

   affect the qualification of the Marital Trust, (b) prevent my

   estate from receiving the benefit of the maximum marital

   deduction, or (c) affect the right of my said wife to all income

   therefrom or her right to dispose of the principal and income

   thereof in the amount and to the extent necessary to qualify the

   Marital Trust for the marital deduction for Federal estate tax

   purposes under the provisions of the law applicable to my

   estate.

The parties have stipulated that Mr. Posner's will included none of the substantive dispositions, such as for income beneficiaries, remaindermen, 2004 Tax Ct. Memo LEXIS 112">*115 and powers of appointment, normally found in a document establishing a testamentary trust.

In 1976, Mr. Posner's estate filed a Federal estate tax return, attaching thereto a copy of Mr. Posner's will. On that return, Mr. Posner's estate claimed a marital deduction with respect to the marital trust property. Respondent audited this estate tax return and allowed the claimed marital deduction.

Decedent's Will

Before her death, decedent and her two daughters (the daughters) had a falling out. In her will, dated January 3, 1996, decedent effectively disinherited the daughters, leaving most of her estate to her son David, his family, and three charities. ² In her will, decedent directed the marital trust property, valued at approximately $ 5 million, to be paid into a revocable trust (the revocable trust). To one daughter decedent left $ 100; to the other daughter she left only a photograph. The daughters unsuccessfully challenged the will's validity. ³

2004 Tax Ct. Memo LEXIS 112">*116 Power of Appointment Case

While the daughters' challenge to the validity of decedent's will was ongoing, decedent's children disputed ownership of the marital trust property. The daughters contended that decedent had possessed no power of appointment over the marital trust property and that, therefore, the property should revert to Mr. Posner's estate to be distributed equally to the three children pursuant to the residuary clause in Mr. Posner's will. David, as decedent's personal representative and trustee of decedent's revocable trust, contended that decedent possessed and exercised a general power of appointment over the marital trust property and, therefore, the property should be distributed to the various charitable organizations and other beneficiaries named in decedent's revocable trust instrument.

Seeking to resolve this matter, the trustee of Mr. Posner's estate filed a complaint for declaratory judgment in the Circuit Court for Baltimore County, Maryland (Baltimore County circuit court), naming decedent's three children as defendants. On August 11, 1997, the Baltimore County circuit court granted summary judgment for the daughters, ruling that the marital trust property2004 Tax Ct. Memo LEXIS 112">*117 was not part of decedent's estate but instead reverted to Mr. Posner's estate:

     The Court finds as a matter of law that, when Mr. Posner's



   Will is read in its entirety, Item XIV grants Mrs. Posner power



   over the Marital Trust. However, this power is limited to



   inter vivos because ambiguous granting language must be



   construed only as broadly as is necessary to fulfill the

   testator's intent. See Hutchinson v. Farmer, [190 Md. 411">190 Md. 411, 58 A.2d 638] (1948)

   Furthermore, the fact that the IRS approved the marital



   deduction did not establish that Mrs. Posner's powers were

   greater than inter vivos because the Trust would have qualified

   for the deduction if Mrs. Posner had either inter vivos or testamentary power.

 As Mrs. Posner's powers over the Marital Trust were limited

   to inter vivos, her attempt to fund the Revocable Trust

   with assets from the Marital Trust fails. The Revocable Trust,

   by its terms, is not an exercise of inter vivos power



   because it could not vest until Mrs. Posner's death.



   Accordingly, Mrs. Posner's Revocable

2004 Tax Ct. Memo LEXIS 112">*118 Trust was an attempt to

   exercise a testamentary power that she did not possess.



     The Court concludes that the assets from the Marital Trust therefore



   revert to Mr. Posner's estate to be distributed according to the residuary clause

   in his Will. [McDonagh v. Geduldig, No. C-97-001002 (Baltimore County Cir. Ct. Aug. 11, 1997).]

 

The Maryland Court of Special Appeals (court of special appeals) affirmed the Baltimore County circuit court's ruling that Mr. Posner's will granted decedent no testamentary power of appointment. Posner v. McDonagh, No. 3C971002 (Md. Ct. Spec. App. Mar. 11, 1997). The court of special appeals was unpersuaded that references in Mr. Posner's will to the Federal estate tax marital deduction evinced his intention to grant decedent a testamentary power of appointment:

     The statements in Item XIV of Nathan Posner's will are very

   general; they simply demonstrate that he wanted to qualify the

   marital trust for the marital deduction. In light of the

   broadness of these pronouncements, and in light of the fact that

   a marital trust will qualify for the marital2004 Tax Ct. Memo LEXIS 112">*119 deduction if the

   surviving spouse is given either an inter vivos power of

   appointment or a testamentary power of appointment, it is not at

   all clear that the statements in Item XIV of Nathan Posner's

   will evince an intent to grant Rose Posner a testamentary power

   of disposition over the marital trust's assets. Given the

   generality of the statements, it is almost as easy to conclude

   that Nathan Posner intended to grant Rose Posner a solely

   inter vivos power of appointment as it is to conclude

   that he intended to grant her a testamentary power of

   appointment. Thus, the language in Item XIV of the will does not

   provide conclusive proof of Nathan Posner's intent with respect

   to Rose Posner's power of appointment over the marital trust's

   assets.

Furthermore, the court of special appeals stated that under applicable Maryland caselaw, the language in Mr. Posner's will "is insufficient to grant Rose Posner either an inter vivos or a testamentary power of appointment over the marital trust's assets." Id. ⁴ The court of special appeals stated its holding as follows: "Accordingly, we hold2004 Tax Ct. Memo LEXIS 112">*120 that Nathan Posner's will did not grant Rose Posner a testamentary power of appointment over the assets of the marital trust." Id.

By order dated June 30, 1999, the Maryland Court of Appeals, Maryland's highest court, declined to hear the appeal of the court of special appeals' decision.

The Estate's Federal Estate Tax Return

While the above-described litigation was pending, David, as personal representative of decedent's estate, filed a request for an extension of time to file the estate's Federal estate tax return and remitted estate tax of $ 6.5 million. On July 30, 1998, notwithstanding the uncertainty of the outcome of the State court litigation, David filed the estate's Federal estate tax return, wherein the marital trust property was included in2004 Tax Ct. Memo LEXIS 112">*121 decedent's gross estate. ⁵

On2004 Tax Ct. Memo LEXIS 112">*122 July 12, 2000, the estate filed a claim for an estate tax refund of $ 2,909,000, on the ground that the litigation in the Maryland State courts had proved the inclusion of the marital trust property in decedent's gross estate (as reported on the estate's estate tax return) to have been in error. On July 10, 2001, respondent issued a notice of deficiency disallowing the refund claim. ⁶

                OPINION

Section 2001 imposes an estate tax determined, in part, by the value of the taxable estate. Sec. 2001(b). The taxable estate is defined as the gross estate less deductions. Sec. 2051. The gross estate generally includes the value of any property with respect to which the decedent has a general power of appointment at the time of his or her death. 2004 Tax Ct. Memo LEXIS 112">*123 Sec. 2041(a)(2). With exceptions inapplicable here, a general power of appointment is defined as a power that is exercisable in favor of the decedent, the decedent's estate, the decedent's creditors, or the creditors of the decedent's estate. Sec. 2041(b)(1).

A power to make an inter vivos appointment of property is a general power of appointment if it is exercisable in favor of the decedent or the decedent's creditors, regardless of whether the power is also exercisable in favor of the decedent's estate or the creditors of the decedent's estate. Jenkins v. United States, 428 F.2d 538">428 F.2d 538, 428 F.2d 538">544-545 (5th Cir. 1970); Estate of Edelman v. Commissioner, 38 T.C. 972">38 T.C. 972, 38 T.C. 972">976-977 (1962); see also Martin v. United States, 780 F.2d 1147">780 F.2d 1147, 780 F.2d 1147">1148 n. 1 (4th Cir. 1986); Condon Nat'l Bank v. United States, 349 F. Supp. 755">349 F. Supp. 755, 349 F. Supp. 755">759-760 (D. Kan. 1972); sec. 20.2041-1(c), Estate Tax Regs.

As discussed below, the court of special appeals has ruled that Mr. Posner's will granted decedent no testamentary power of appointment over the marital trust2004 Tax Ct. Memo LEXIS 112">*124 property. Respondent does not dispute that ruling. Respondent contends, however, that Mr. Posner's will granted decedent an inter vivos general power of appointment over the marital trust property so as to make it includable in her gross estate pursuant to section 2041(a). The estate argues that under applicable Maryland law, as adjudicated by the court of special appeals, decedent possessed no power of appointment over the marital trust property. Accordingly, the estate contends, inclusion of the marital trust property in decedent's gross estate, as reported on the estate's estate tax return, was in error.

State law, which creates legal interests and rights in property, including powers of appointment, determines the nature, scope, and validity of such legal interests and rights. See Morgan v. Commissioner, 309 U.S. 78">309 U.S. 78, 309 U.S. 78">80, 84 L. Ed. 585">84 L. Ed. 585, 60 S. Ct. 424">60 S. Ct. 424 (1940); Estate of Pierpont v. Commissioner, 336 F.2d 277">336 F.2d 277, 336 F.2d 277">281 (4th Cir. 1964), affg. T.C. Memo. 1962-286; Estate of Allen v. Commissioner, 29 T.C. 465">29 T.C. 465, 29 T.C. 465">467- 468 (1957). Federal law, in turn, determines the Federal taxation of such interests or rights. 309 U.S. 78">Morgan v. Commissioner, supra.2004 Tax Ct. Memo LEXIS 112">*125 ⁷

"[T]he highest court of the state is the final arbiter of what is state law. When it has spoken, its pronouncement is to be accepted by federal courts as defining state law". West v. Am. Tel. & Tel. Co., 311 U.S. 223">311 U.S. 223, 311 U.S. 223">236, 85 L. Ed. 139">85 L. Ed. 139, 61 S. Ct. 179">61 S. Ct. 179 (1940). On the other hand, we are not necessarily bound to follow decisions of State intermediate appellate courts. Commissioner v. Estate of Bosch, 387 U.S. 456">387 U.S. 456, 387 U.S. 456">465, 18 L. Ed. 2d 886">18 L. Ed. 2d 886, 87 S. Ct. 1776">87 S. Ct. 1776 (1967);2004 Tax Ct. Memo LEXIS 112">*126 Estate of Rapp v. Commissioner, 140 F.3d 1211">140 F.3d 1211, 140 F.3d 1211">1216 (9th Cir. 1998), affg. and remanding on another ground T.C. Memo. 1996-10; Estate of Harper v. Commissioner, 93 T.C. 368">93 T.C. 368, 93 T.C. 368">374 (1989); Estate of Pangas v. Commissioner, 52 T.C. 99">52 T.C. 99, 52 T.C. 99">101 (1969). Instead, we give "proper regard" to decisions of State intermediate appellate courts if these decisions are on point. See 387 U.S. 456">Commissioner v. Estate of Bosch, supra; Estate of Casey v. Commissioner, 948 F.2d 895">948 F.2d 895, 948 F.2d 895">898 (4th Cir. 1991), revg. T.C. Memo. 1989-511; Ward v. Commissioner, 87 T.C. 78">87 T.C. 78, 87 T.C. 78">91-92 (1986); Estate of Fulmer v. Commissioner, 83 T.C. 302">83 T.C. 302, 83 T.C. 302">306 (1984). Therefore, in deciding whether decedent possessed a general power of appointment, relevant decisions of the Maryland Court of Appeals are binding on this Court. Decisions of the court of special appeals, on the other hand, are not binding; these decisions, if on point, are entitled to "proper regard".

In Posner v. McDonagh, No. 3C971002 (Md. Ct. Spec. App. Mar. 11, 1999), the court of special appeals held that decedent possessed no testamentary power of appointment. The2004 Tax Ct. Memo LEXIS 112">*127 estate relies heavily on the statement in the court of special appeals' unreported opinion that Mr. Posner's will was "insufficient to grant Rose Posner either an inter vivos or a testamentary power of appointment over the marital trust's assets." Id. This statement, however, is dicta; the only issue before the court of special appeals was whether decedent possessed a testamentary power of appointment. Indeed, in a subsequent published opinion involving the apportionment of taxes relating to the marital trust property, the court of special appeals characterized its prior statement as dicta:

     On appeal, this Court held that Rose did not have a



   testamentary power of appointment over the assets of the Marital

   Trust, and affirmed the trial court. In dicta, we also

   stated that the language of Nathan's will was "insufficient to



   grant Rose Posner either an inter vivos or a testamentary power of appointment . . . ."

   [Gordon v. Posner, 790 A.2d 675, 679, 142 Md. App. 399">142 Md. App. 399 (Md. Ct. Spec. App. 2002)

   ; emphasis added.]

Consequently, although we give the decisions of the court of special appeals proper regard, those decisions do not squarely answer2004 Tax Ct. Memo LEXIS 112">*128 the question whether decedent possessed an inter vivos power of appointment over the marital trust property.

On reply brief, respondent argues that the only Maryland decision that is "legally effective" with respect to this question is the ruling of the Baltimore County circuit court, which held that decedent lacked a testamentary power of appointment over the marital trust property and stated in part: "when Mr. Posner's Will is read in its entirety, Item XIV grants Mrs. Posner power over the Marital Trust. However, this power is limited to inter vivos". McDonagh v. Geduldig, No. C-97-001002 (Baltimore County Cir. Ct. Aug. 11, 1997).

As a threshold matter, we note that the Baltimore County circuit court is a State trial court, not an intermediate State appellate court. Although decisions of a State trial court are given some weight and proper regard if on point, see 387 U.S. 456">Commissioner v. Estate of Bosch, supra at 465, we must carefully consider the nature of the trial court litigation, see Estate of Ahlstrom v. Commissioner, 52 T.C. 220">52 T.C. 220, 52 T.C. 220">229 (1969), and the subsequent proceedings on appeal.

In ruling that Mr. Posner's will gave decedent no testamentary power,2004 Tax Ct. Memo LEXIS 112">*129 the Baltimore County circuit court stated that item XIV of Mr. Posner's will was a granting clause that granted decedent only an inter vivos power of appointment. ⁸ In its affirmance, the court of special appeals relied on the lack of specificity in Mr. Posner's will regarding the claimed testamentary power of appointment. The court of special appeals did not endorse the circuit court's statement that item XIV was a granting clause that granted decedent an inter vivos power of appointment.

To the contrary, as previously discussed, in holding that Mr. Posner's will gave decedent no testamentary power of appointment, the court of special appeals stated2004 Tax Ct. Memo LEXIS 112">*130 in dicta that Mr. Posner's will was "insufficient to grant Rose Posner either an inter vivos or a testamentary power of appointment over the marital trust's assets." Posner v. McDonagh, supra.In light of this statement, and considering the basis on which the court of special appeals affirmed the circuit court's ruling, we are reluctant to assign much weight to the Baltimore County circuit court's statement that Mr. Posner's will granted decedent an inter vivos power of appointment over the marital trust property. To the contrary, we believe that the Baltimore County circuit court's conclusions in this regard were effectively set aside by the court of special appeals. Cf. Hudson v. Commissioner, 100 T.C. 590">100 T.C. 590, 100 T.C. 590">594 (1993) (stating that for purposes of applying collateral estoppel, "where a trial court's conclusions of law or findings of fact are not passed on by the appellate court, the trial court's conclusions of law or findings of fact are effectively set aside").

Finding no other rulings of Maryland courts that are dispositive in determining whether Mr. Posner's will granted decedent an inter vivos general power of appointment, we must make our best effort to determine2004 Tax Ct. Memo LEXIS 112">*131 how Maryland's highest court would decide the issue. See Commissioner v. Estate of Bosch, 387 U.S. 456">387 U.S. at 465; West v. Am. Tel. & Tel. Co., 311 U.S. 223">311 U.S. at 237; 948 F.2d 895">Estate of Casey v. Commissioner, supra at 898.

A threshold issue is whether Mr. Posner's will conferred upon decedent any sort of a power of appointment -- testamentary or inter vivos, general or limited. The parties have stipulated that Mr. Posner's will "did not include any of the substantive dispositions, such as income beneficiaries, remaindermen, and powers of appointment, normally found in a document establishing a testamentary trust." (Emphasis added.) The holding of both Maryland courts to adjudicate the issue was that Mr. Posner's will created no testamentary power of appointment. Inasmuch as Mr. Posner's will contains no substantive provisions regarding powers of appointment of any sort, we are persuaded that Mr. Posner's will also failed to create an inter vivos power of appointment (as the court of special appeals stated in dicta).

Respondent argues that the failure of item II of Mr. Posner's will to provide substantive dispositions of income and principal is a "scrivener's2004 Tax Ct. Memo LEXIS 112">*132 error" and that items II and XIV of Mr. Posner's will, when read together, clearly establish his intent to create a trust and grant decedent "a right to all trust income, and a general power of appointment over the trust, such that the trust would qualify for the Federal estate tax marital deduction." We are unpersuaded that the absence of substantive dispositions should be regarded as a mere scrivener's error. Rather, we believe that because of the lack of such dispositions, the will fails to confer on decedent a power of appointment with respect to the marital trust property. We discern in Mr. Posner's will a directive that the marital trust property should qualify for the Federal estate tax marital deduction. The will does not provide, however, the necessary terms for satisfying this directive. Reading Mr. Posner's will as respondent suggests would be tantamount to rewriting Mr. Posner's will to include these provisions, which we are not at liberty to do. See Gaither v. Fidelity-Baltimore Nat'l Bank & Trust Co., 208 Md. 8">208 Md. 8, 115 A.2d 711 (Md. 1955). ⁹

2004 Tax Ct. Memo LEXIS 112">*133 Items II and XIV of Mr. Posner's will refer to the Federal estate tax marital deduction. On this basis, respondent argues that this case comes squarely within the rationale of Guiney v. United States, 425 F.2d 145">425 F.2d 145 (4th Cir. 1970). In 425 F.2d 145">Guiney v. United States, supra at 147, the testator used the words "general power of appointment" to describe the power given to his wife and referenced "the marital deduction as provided by the Internal Revenue Code of 1954". The Court of Appeals for the Fourth Circuit found that this "unmistakably precise language" manifested "a clear and forthright desire to clothe his widow with the 'general power of appointment' necessary to accomplish the marital deduction and by express reference brought the power he created squarely within the Code's requirements." 425 F.2d 145">Id. at 149. The Court of Appeals concluded:

   Thus, the widow here is given specific authorization to appoint



   to herself or her estate, as the testator obviously was not

   referring to a Maryland (limited) general power of appointment.

   By his use of the words "general power of appointment,"

   coupled with his expressed "intention2004 Tax Ct. Memo LEXIS 112">*134 to take advantage of

   the marital deduction as provided by the Internal Revenue Code



   of 1954," the testator was clearly referring to the general

   power of appointment provisions of section 2041 of the Code,

   which empower the donee to appoint to herself or her estate.

   [425 F.2d 145">Id. at 150.]

Unlike the will in 425 F.2d 145">Guiney, Mr. Posner's will contains no language referring to a "general power of appointment" and, indeed, contains no substantive dispositions of the marital trust property. Item II of Mr. Posner's will does not expressly provide for the disposition of income or principal of the marital trust, and it contains no direction regarding the distribution of principal upon termination of the trust. It refers only to the Federal estate tax marital deduction. Item XIV also refers to the marital deduction but contains no language that we might reasonably interpret to grant decedent a general power of appointment. The references to the marital deduction alone in items II and XIV are insufficient to create a general power of appointment in decedent's favor. See Estate of Pierpont v. Commissioner, 336 F.2d 277">336 F.2d at 281.

In2004 Tax Ct. Memo LEXIS 112">*135 conclusion, we defer to the ruling of the court of special appeals that Mr. Posner's will gave decedent no testamentary power of appointment. Moreover, we believe that the Maryland Court of Appeals would conclude, as the court of special appeals stated in dicta, that the language in Mr. Posner's will was also insufficient to give decedent an inter vivos power of appointment over the marital trust property. Consequently, we hold that decedent possessed no general power of appointment for purposes of section 2041(a)(2).

On its estate tax return, Mr. Posner's estate claimed a marital deduction for the marital trust property. ¹⁰ In doing so, respondent contends, Mr. Posner's estate represented that decedent possessed a general power of appointment over the marital trust property. ¹¹ Respondent argues that the duty of consistency precludes decedent's estate from now taking the contrary position, upon which its claim for refund is predicated, that decedent possessed no general power of appointment. ¹² As explained below, we disagree.

2004 Tax Ct. Memo LEXIS 112">*136 As developed in caselaw, the duty of consistency (sometimes called quasi-estoppel) prevents a taxpayer from benefiting in a later year from an error or omission in an earlier year that cannot be corrected because the time to assess tax for the earlier year has expired. Estate of Letts v. Commissioner, 109 T.C. 290">109 T.C. 290, 109 T.C. 290">296 (1997), affd. without published opinion 212 F.3d 600">212 F.3d 600 (11th Cir. 2000). The duty of consistency may apply if: (1) The taxpayer made a representation of fact or reported an item for tax purposes in one tax year; (2) the Commissioner acquiesced in or relied on that fact for that year; and (3) the taxpayer desires to change the representation previously made in a later tax year after the earlier year has been closed by the statute of limitations. 109 T.C. 290">Id. at 297; LeFever v. Commissioner, 103 T.C. 525, 543 (1994), affd. 100 F.3d 778">100 F.3d 778 (10th Cir. 1996).

Spouses, as well as their estates, may have sufficient identity of interests so that one may be estopped under the duty of consistency by a prior representation of the other. 109 T.C. 290">Estate of Letts v. Commissioner, supra at 298; Cluck v. Commissioner, 105 T.C. 324">105 T.C. 324, 105 T.C. 324">333-336 (1995).2004 Tax Ct. Memo LEXIS 112">*137 Respondent contends that Mr. Posner's estate and decedent's estate have sufficient identity of interests that the duty of consistency is applicable. For purposes of this discussion, we assume, without deciding, that there was privity of interest between Mr. Posner's estate and decedent's estate.

On brief, respondent acknowledges that the duty of consistency applies "if the inconsistency is a question of fact or a mixed question of fact and law. It does not apply to mutual mistake on the part of a taxpayer and the Service concerning a pure question of law." See LeFever v. Commissioner, 100 F.3d 778">100 F.3d at 788; Herrington v. Commissioner, 854 F.2d 755">854 F.2d 755, 854 F.2d 755">758 (5th Cir. 1988), affg. Glass v. Commissioner, 87 T.C. 1087">87 T.C. 1087 (1986); Southern Pacific Transp. Co. v. Commissioner, 75 T.C. 497">75 T.C. 497, 75 T.C. 497">560 (1980); Unvert v. Commissioner, 72 T.C. 807">72 T.C. 807, 72 T.C. 807">816 (1979), affd. 656 F.2d 483">656 F.2d 483 (9th Cir. 1981). ¹³ With little elaboration, respondent contends on brief that the inconsistency in question here is a "mixed question of fact and law", so that the duty of consistency applies. We disagree.

2004 Tax Ct. Memo LEXIS 112">*138 In Crosley Corp. v. United States, 229 F.2d 376">229 F.2d 376, 229 F.2d 376">380 (6th Cir. 1956), the Court of Appeals for the Sixth Circuit noted that the duty of consistency "is probably applicable in cases where the factual situation is such as to justify the taxpayer in taking either of two possible positions" but generally does not apply "when the error is one of law arising out of a definite factual situation". In the instant case, the inconsistency arose because of a mutual mistake in deciding how Mr. Posner's will should be construed under Maryland law -- a purely legal issue. See McIntyre v. Byrne, 217 Md. 71">217 Md. 71, 141 A.2d 692, 695 (Md. 1958) ("The construction of a will is a matter of law for the court to determine"). Mr. Posner's estate did not misrepresent the property or type of property that Mr. Posner had devised to decedent. Respondent has not alleged any facts to show that the estate has been inconsistent with respect to any factual positions or to suggest that the inconsistency in question arose from anything other than a purely legal error in the context of "a definite factual situation". 229 F.2d 376">Crosley Corp. v. United States, supra at 380. ¹⁴

2004 Tax Ct. Memo LEXIS 112">*139 Moreover, the duty of consistency "does not apply where all pertinent facts are known to both the Commissioner and the taxpayer", especially if "the crucial facts are known to both parties and the erroneous deductions are due to a mutual mistake of law." 75 T.C. 497">Southern Pacific Transp. Co. v. Commissioner, supra at 560; cf. Interlochen Co. v. Commissioner, 232 F.2d 873">232 F.2d 873 (4th Cir. 1956), affg. 24 T.C. 1000">24 T.C. 1000 (1955); Hull v. Commissioner, 87 F.2d 260">87 F.2d 260, 87 F.2d 260">262 (4th Cir. 1937) (stating that "a party either knowing the facts, or in a position to know them, cannot claim the benefit of estoppel"), revg. 33 B.T.A. 178">33 B.T.A. 178 (1935). In the instant case, respondent had reason to know all the relevant facts. When Mr. Posner's estate filed its estate tax return, it adequately disclosed the relevant facts and documents, attaching a copy of Mr. Posner's will. ¹⁵ Respondent audited the estate tax return of Mr. Posner's estate and allowed the marital deduction. ¹⁶ Respondent has not alleged any facts to suggest that this audit was insufficient in any regard other than in the failure to apply the law correctly. Under these circumstances, respondent cannot be viewed2004 Tax Ct. Memo LEXIS 112">*140 as justifiably relying on the legal representation on the estate tax return of Mr. Posner's estate.

2004 Tax Ct. Memo LEXIS 112">*141 The executor of Mr. Posner's estate and the executor of decedent's estate, as well as respondent's agents upon audit of Mr. Posner's estate's estate tax return, all acted in accordance with the mutual mistake of law that Mr. Posner's will gave decedent a general power of appointment. Indeed, when he filed the estate tax return of decedent's estate, decedent's executor included the marital trust property in decedent's gross estate and paid the resulting estate tax. He steadfastly maintained in the State court litigation that decedent possessed a testamentary power of appointment over the marital trust property. Only after the court of special appeals rejected this position and the Maryland Court of Appeals declined to hear the appeal did he file the refund claim. Respondent has not carried his burden to show that the duty of consistency should apply in these circumstances.

Accordingly, we hold that the marital trust property is not includable in decedent's gross estate.

The estate requests that we award it interest on its overpayment of estate tax pursuant to sections 6611 and 6621. This Court generally does not have jurisdiction to enter2004 Tax Ct. Memo LEXIS 112">*142 a decision for interest upon an overpayment. Estate of Baumgardner v. Commissioner, 85 T.C. 445">85 T.C. 445, 85 T.C. 445">452-453 (1985); Harrison v. Commissioner, T.C. Memo. 1994-614; see sec. 6512(b)(1). As an exception to this general rule, however, section 6512(b)(2) provides that if the Secretary fails "to refund the overpayment determined by the Tax Court, together with the interest thereon as provided in subchapter B of chapter 67, then the Tax Court upon motion by the taxpayer, shall have jurisdiction to order the refund of such overpayment and interest."

The estate makes no allegation that it paid the interest it claims or that this interest is part of its overpayment of estate tax. Cf. 38 T.C. 972">Estate of Baumgardner v. Commissioner, supra.On the contrary, the claimed interest appears to be interest that has accrued upon its overpayment. Likewise, this case does not involve interest on an overpayment that the Commissioner has credited or refunded. Cf. Sunoco, Inc. v. Comm'r, 122 T.C. 88">122 T.C. 88 , 122 T.C. No. 4">122 T.C. No. 4, 2004 U.S. Tax Ct. LEXIS 4">2004 U.S. Tax Ct. LEXIS 4 (2004) (holding that under certain circumstances this Court has overpayment jurisdiction under section 6512(b) with regard to overpayment interest in the case2004 Tax Ct. Memo LEXIS 112">*143 of overpayments credited or refunded by the Commissioner).

We hold that we do not have jurisdiction at this juncture to enter a decision for interest upon the estate's overpayment of estate tax.

Because of concessions by the parties and the fact that the estate is claiming an overpayment,

Decision will be entered under Rule 155.