concurring in part and dissenting in part.
I dissent from that portion of the majority opinion holding that the Lloyds should not enjoy the protection against an “unexpected decision” granted Missouri taxpayers by § 143.903. I concur with the majority opinion in all other respects.
While the majority resorts to legislative history to interpret § 143.903, I do not believe any ambiguity exists. The statute defines “unexpected” as “a reasonable person would not have expected the decision or order based on prior law, previous policy or regulations of the department of revenue.” The word “expect” has been defined to mean that an individual realizes or should realize “a strong probability the consequences in question would result.” Farm Bureau Town and Country Ins. v. Turnbo, 740 S.W.2d 232, 236 (Mo.App.1987); City of Carter Lake v. Aetna Cas. and Sur., 604 F.2d 1052, 1058 (8th Cir.1979).
I believe the majority misreads § 143.903 in requiring that the taxpayers show that the decision was unexpected. Instead, the statute by its plain terms defines “unexpected” only to require a showing that the decision was not expected. Had the legislature intended the result reached by the majority, it would have deleted the bracketed language below and stated:
2. The provisions of this section shall apply only to final decisions by or orders of a court of competent jurisdiction or the administrative hearing commission which are rendered after October 1,1990, and which are determined by the court or the administrative hearing commission rendering the decision, or subsequently by a lower court or the administrative hearing commission, to be unexpected[. For the purposes of this section the term “unexpected” shall mean that a reasonable person would not have expected the decision or order] based on prior law, previous policy or regulation of the department of revenue.
The inclusion of the bracketed language, however, mandates a different interpretation. Thus, contrary to the position taken *525by the majority, the Lloyds are entitled to the protection of § 148.903 unless it is shown that at the time of filing their returns a reasonable person should have realized there was a “strong probability” of the decision herein, based upon the prior law.
On the record below, the Lloyds clearly established that this decision was not expected when they filed. First, Wolff v. Director of Revenue, 791 S.W.2d 390 (Mo. banc 1990), had not been decided at that time. Second, the Lloyds point out that § 143.451.2, the statute providing for the single-factor formula for apportioning income, specifically refers to corporations described in § 143.441.1(1). That statute applies by its express terms to “Every corporation”. This would ordinarily be understood to include subchapter S corporations. Thus, the Lloyds had an objective and reasonable basis, grounded in statute, to justify their conclusion. Finally, the Lloyds showed that both prior to the Wolff decision and while the Wolff case was pending, the Department of Revenue reviewed returns filed by the Lloyds and utilized the same apportionment method they used in calculating refunds. If the department had expected a contrary treatment, they would have acted accordingly.
The only responsive evidence put forward by the Department of Revenue was that it had issued notices of adjustments to the Wolffs regarding the same issue on November 13, 1987. The department implies that the Lloyds should, therefore, have expected similar treatment. The department’s argument fails, however, because it did not follow the same procedure with the Lloyds as it did with the Wolffs. Had the department itself acted similarly with all known S corporation taxpayers who apportioned income, all would have been put on notice regarding their expectations. By only proceeding against the Wolffs, and not against other similarly situated taxpayers, the department clearly established its own determination that this was a test case and not one with an expected result.
For corporations, individuals, and the state itself, the predictability of tax liability or tax revenues is crucially important. The effect of retroactive application of interpretations of our tax laws can create significant hardships and disruptions. By enacting § 143.903, the Missouri legislature attempted to assist all parties by removing from them the risk of decisions that would not have been expected. While the Lloyds may not escape the future consequences of the Wolff decision, § 143.903 should protect them from the retroactive application of a first impression decision of this Court that they did not expect when they filed their return.