Appeal from the Circuit Court of Cook County Honorable Joanne L. Lanigan, Judge Presiding.
 The opinion of the court was delivered by: Presiding Justice O'mara Frossard
 Plaintiff Hercules, Inc., filed a two-count second amended complaint for administrative review against defendants the Illinois Department of Revenue and Kenneth Zehnder, the Department's director, after the Department found plaintiff owed taxes on a $1.3 billion capital gain it earned in 1987. Count I of the complaint sought reversal of the Department's finding of deficiency, and count II sought attorney fees under section 7 of the Taxpayers' Bill of Rights Act (Act) (20 ILCS 2520/7 (West 2000)). The circuit court entered an order affirming the Department's finding of deficiency. Plaintiff appealed the circuit court's order, and we in turn reversed the circuit court's finding of deficiency. See Hercules, Inc. v. Department of Revenue, 324 Ill. App. 3d 329 (2001), appeal denied, 197 Ill. 2d 560 (2001). After we issued the mandate returning the case to the circuit court, plaintiff filed a motion requesting the circuit court to reinstate its claim for attorney fees and enter summary judgment in its favor on that claim. The trial court entered an order reinstating plaintiff's claim for attorney fees, but denied its motion for summary judgment and dismissed its action. Plaintiff now appeals that order, contending that the trial court improperly denied its motion and dismissed its attorney fee claim because the Department did not have reasonable cause under section 7 of the Act to issue the notice of deficiency.
 In 1987, plaintiff, a global chemical manufacturing and aerospace company doing business in Illinois, sold its interest in a joint-venture, known as Himont, and realized a $1.3 billion gain from that sale. Plaintiff reported the gain as nonbusiness income on its 1987 Illinois income tax return. After auditing plaintiff and determining that this capital gain constituted business income, the Department issued a notice of deficiency for additional taxes, interest, and penalties. Plaintiff filed a protest, and an administrative law judge (ALJ) subsequently conducted a hearing at which evidence was presented regarding the formation of Himont and its relationship to plaintiff. Plaintiff contended in a post-hearing memorandum that it was not operationally integrated with Himont after Himont's formation, and thus the gain from the sale of its stock in the joint venture was not constitutionally apportionable in Illinois.
 Following the hearing, the ALJ recommended that the Department sustain the notice of tax deficiency. The ALJ found that the capital gain income qualified as business income under section 1501(a)(1) of the Illinois Income Tax Act (Tax Act) (35 ILCS 5/1501(a)(1) (West 2000)). The ALJ observed that courts apply either a transactional or functional test when applying section 1501(a)(1) of the Tax Act. The ALJ found that the gain qualified as business income under the transactional test because creating and selling joint-ventures was a regular practice of plaintiff.
 The ALJ also found that the capital gain qualified as business income under the functional test because Himont was an asset used in plaintiff's regular trade or business. The ALJ reasoned that the income received by plaintiff was not just a result of a sale of stock but of the transfer of its entire polypropylene operation to Himont. The ALJ next found a unitary business relationship existed between plaintiff and Himont's manufacture and sale of polypropylene. The ALJ thus believed that because plaintiff and Himont were functionally integrated, they had a sufficient nexus with Illinois to allow the Department to tax plaintiff's income from the sale of stock. The Department adopted the ALJ's decision.
 Plaintiff filed a petition for administrative review in the circuit court, and the circuit court in turn affirmed the Department's decision. The circuit court agreed with the ALJ that there was a unitary business relationship between Himont and plaintiff. The court found that the Himont stock sold by plaintiff was an integral part of its regular trade or business operations and thus qualified as business income under the functional test.
 The circuit court subsequently granted a motion for reconsideration filed by plaintiff and vacated its prior decision and order. Thereafter, the court issued a memorandum decision and order affirming the Department's decision "based on different application of the law to the facts from those espoused by the [ALJ]." The circuit court reversed its finding in the previous order that a unitary business relationship existed. The court also reversed its conclusion that the ALJ properly found the transactional test was satisfied. In support of that reversal the court noted the absence of evidence that plaintiff was in the business of forming and divesting itself of joint ventures. Despite its reversal of these findings, the court concluded that the functional test for business income was satisfied. In support of this conclusion, the court noted Himont was not simply a passive investment of plaintiff, but was an asset used in its regular trade and business. The court further noted that the gain from its sale was used for operational functions. The court also concluded that the commerce clause and due process clause of the United States Constitution (U.S. Const., art. I, §8, amend. XIV) did not preclude the Department from taxing the subject gain, based on its finding that "there was an operational function between [plaintiff] and Himont when it surrendered its stock to allow for an initial public offering [which] was a means of supplying financial support to Himont."
 Plaintiff appealed the circuit court's order affirming the tax to this court, and we in turn reversed that order. See Hercules, 324 Ill. App. 3d at 344. In our decision, we noted that the United States Supreme Court has adopted two tests to determine whether a state may apportion income of a nondomiciliary corporation: the "unitary business relationship" test and the "operational function" test. Hercules, 324 Ill. App. 3d at 336, citing Allied-Signal, Inc. v. Director, Division of Taxation, 504 U.S. 768, 787, 119 L. Ed. 2d 533, 552, 112 S. Ct. 2251, 2263 (1992). After noting the Department, in the instant case, acknowledged that the unitary test had not been satisfied, we reviewed the applicability of the operational function test to the income at issue. Hercules, 324 Ill. App. 3d at 336-43. Under the operational function test, a state may apportion income "when the capital transaction serves an operational rather than an investment function." Hercules, 324 Ill. App. 3d at 337. "The relevant inquiry in determining whether a capital transaction involving an asset serves an investment or operational function 'focuses on the objective characteristics of the asset's use and its relation to the taxpayer and its activities within the taxing State.' " Hercules, 324 Ill. App. 3d at 337, quoting Allied-Signal, Inc., 504 U.S. at 785, 119 L. Ed. 2d at 550, 112 S. Ct. at 2262.
 We observed that ASARCO Inc. v. Idaho State Tax Comm'n, 458 U.S. 307, 73 L. Ed. 2d 787, 102 S. Ct. 3103 (1982), was "instructive" in determining whether the operational function test was satisfied. Hercules, 324 Ill. App. 3d at 339. After analyzing the facts presented to the ALJ in light of ASARCO, we found no "significant" distinction between the investment at issue in ASARCO and plaintiff's investment in Himont. Hercules, 324 Ill. App. 3d at 340. Thus, we rejected the Department's argument that "there was a significant flow of value between Hercules and Himont, well beyond what the facts showed in ASARCO." Hercules, 324 Ill. App. 3d at 340. In support of our decision, we also noted that the highest courts in Minnesota and Maryland had each recently reviewed plaintiff's sale of Himont stock, the same transaction before us, and concluded that the capital gain earned from that transaction was not apportionable in the respective states over which those courts presided. Hercules, 324 Ill. App. 3d at 340-41.
 In January 2002, this court issued the mandate transferring this case to the circuit court. In February 2002, plaintiff filed a motion seeking to reinstate and obtain summary judgment on count II of its second amended complaint, which sought attorney fees under the Act. Plaintiff contended in its motion that the Department was required to pay its attorney fees because the Department did not have "reasonable cause" under section 7 of the Act for issuing the deficiency. Plaintiff noted that the term "reasonable cause" under section 7 had not previously been interpreted and argued that it should be construed as it had been under other Illinois tax-related statutory provisions.
 The Department filed a response to plaintiff's motion for summary judgment, contending that it had "reasonable cause" for issuing the deficiency and that "reasonable cause" should be construed in accordance with the standard applied by federal courts to the federal statute upon which the Act was modeled.
 On May 9, 2002, following a hearing on plaintiff's motion, the circuit court entered an order reinstating plaintiff's claim for attorney fees, denying its motion for summary judgment, and dismissing the case. Although the circuit court's order did not expressly state the basis for the dismissal, the court's oral findings, which the written order incorporated, reflect that it dismissed plaintiff's case because the undisputed facts established, as a matter of law, that the Department had "reasonable cause" under section 7 of the Act for issuing the subject notice of deficiency. The court found that the proper standard for determining whether the Department had reasonable cause was whether the Department's position was "substantially justified." The court noted, in reliance upon both federal cases and California state cases, that a "substantially justified" position was one that had a reasonable basis in law and fact. The court rejected plaintiff's argument that the "reasonable cause" language in section 7 had the same meaning as that phrase did under the Illinois statute authorizing imposition of ...