Defendant Edward R. Osborn was convicted in a trial to the court on four counts of fraudulent practice in the second degree in violation of Iowa Code sections 422.25(5), 714.8(10) and 714.10(1) (1979). The charges arose from defendant’s alleged willful failure to file state income tax returns and pay state income taxes for 1978 and 1979. In this appeal he contends that the trial court erred in convicting him despite finding he had no intent to defraud and in holding that the term “willfully” as used in section 422.25 requires only a showing of intentional violation of a known duty.
In material part section 422.25(5) provides:
*69Any person required to ... pay any tax, or to make, sign or file any return or supplemental return, who ... willfully fails to pay such tax, ... or make, sign, or file such return, at the time or times required by law, shall be guilty of a fraudulent practice.
Section 714.8(10) provides that a person who does any act declared by any other section of the Code to be a fraudulent practice is guilty of a fraudulent practice. Section 714.10 provides in material part:
Fraudulent practice in the second degree is the following:
1. A fraudulent practice where the amount of money or value of property or services involved exceeds five hundred dollars but does not exceed five thousand dollars.
In the present case the parties stipulated that defendant, who is a lawyer, was required to file Iowa income tax returns for 1978 and 1979, that he did not file returns or pay the tax on time for those years, and that he owed more than $500 but less than $5,000 in state income taxes for each of those years. Defendant urged a defense of diminished responsibility. He offered evidence that he was suffering from severe depression at the times involved, that the condition caused him to procrastinate and avoid stressful situations, that he had no intention to deceive or gain by failing to file tax returns and pay taxes in timely fashion, and that he had no malicious intent.
The trial court made certain relevant findings of fact that are not challenged:
15. The evidence is clear that defendant was certainly capable of performing in a competent manner his duties as an attorney prior to the beginning of his emotional problems.
16. Defendant knew of all applicable deadlines and filing requirements for his 1978 and 1979 tax returns and was aware of the payment deadlines.
17. The court specifically finds that the defendant had no evil motive, or intent to defraud the State of Iowa by not filing the returns or paying the tax.
18. The court finds that the defendant was aware of his duty to file a tax return in 1978 and 1979 and to pay the tax due and that he did not do so.
19. The failure to file and to pay the tax due was not accidental or inadvertent.
Based on the stipulated facts and these findings, the trial court found defendant guilty as charged. In doing so, the court held that the term “willfully” in section 422.25(5) “requires only a general intent as it relates to the failure to file a tax return and/or to pay the tax owed.” The court added: “All that is required is that there be an intentional violation of a known legal duty.”
Defendant’s only contentions and arguments on appeal concern his claims that the court could not lawfully have convicted him after finding that he lacked intent to defraud and that the court erred in equating willfulness with an intentional violation of a known duty. He does not contend or argue that the court’s degree-of-guilt finding was incorrect or that the amount of money “involved” did not meet the degree-of-guilt standard in section 714.10(1).
I. Absence of intent to defraud. Before adoption of the present criminal code, section 422.25(5) provided that the described offenses were indictable misdemeanors, punishable by imprisonment in the county jail not to exceed one year, by a fine not exceeding $2500, or both. See Iowa Code § 422.25(5) (1975). During the comprehensive statutory criminal law revision effective January 1, 1978, the present provision that the offender “shall be guilty of a fraudulent practice” was substituted for the prior penalty language. See § 422.-25(5) (Supp.1977).
Defendant asserts that a necessary consequence of designating the crimes in section 422.25(5) as fraudulent practices is to make intent to defraud an essential element of the offenses charged. We do not agree. We start with the premise that changes made by revision of a statute will not be construed as altering the law unless *70the legislature’s intent to accomplish a change in its meaning is clear and unmistakable. Emery v. Fenton, 266 N.W.2d 6, 10 (Iowa 1978). The revision of section 422.25(5) clearly and unmistakably changed the penalty provision but not the elements of the offenses.
Defendant’s contention depends on an argument that the labeling of the offenses as fraudulent practices necessarily converted them to specific intent crimes. One basic flaw in this argument is that even the offenses specified as fraudulent practices in section 714.8 do not all require proof of intent to defraud. See Dunahoo, The New Iowa Criminal Code, 29 Drake L.Rev. 237, 383-84 (1979-1980).
We find no basis for holding that the General Assembly added the element of intent to defraud to the offenses charged in this case merely by designating the offenses as fraudulent practices. We hold that the designation was made for penalty purposes only.
II. The meaning of willfully. Defendant's second contention is that the word “willfully” contained in section 422.25(5) should be interpreted to require proof of evil motive or intent rather than a mere knowing failure to comply with the filing and payment provisions of the inconjie tax statutes. The trial court rejected this contention and held that willfulness was established by proof of a voluntary and intentional violation of a known legal duty. The court’s findings were consistent with this view of the law.
The same standard of willfulness has been adopted by federal courts in interpreting analogous provisions of federal revenue laws. See, e.g., United States v. Pomponio, 429 U.S. 10, 12-13, 97 S.Ct. 22, 23-24, 50 L.Ed.2d 12, 15-16 (1976); United States v. Bishop, 412 U.S. 346, 360-61, 93 S.Ct. 2008, 2017, 36 L.Ed.2d 941, 949 (1973); United States v. Rifen, 577 F.2d 1111, 1113 (8th Cir.1978); United States v. Pallan, 571 F.2d 497, 501 (9th Cir.), cert. denied, 436 U.S. 911, 98 S.Ct. 2249, 56 L.Ed.2d 411 (1978); United States v. Dillon, 566 F.2d 702, 703-04 (10th Cir.1977), cert. denied, 435 U.S. 971, 98 S.Ct. 1613, 56 L.Ed.2d 63 (1978).
Defendant suggests that this interpretation of the meaning of willfulness is inconsistent with interpretations under other statutes in State v. Aldrich, 231 N.W.2d 890, 894 (Iowa 1975) (“an intentional act inconsistent with good faith and good intentions”) and Huston v. Huston, 255 Iowa 543, 548, 122 N.W.2d 892, 896 (1963) (“not only intentionally or deliberately done, but with a bad or evil purpose, as in violation of law”). Assuming these interpretations are different, the standard employed by the trial court is consistent with interpretations of the term in other cases. See, e.g., State v. Dunn, 199 N.W.2d 104, 107 (Iowa 1972) (“ ‘willfully’ means purposely, deliberately, intentionally”); State v. Wallace, 259 Iowa 765, 773, 145 N.W.2d 615, 620 (1966) (“ ‘willfully’ ordinarily means intentionally, deliberately or knowingly, as distinguished from accidentally, inadvertently or carelessly”). The interpretation obviously depends in part on the statutory context. See Eggman v. Scurr, 311 N.W.2d 77, 78 (Iowa 1981).
Pursuaded by the interpretation given the term by the federal courts under analogous statutes, we believe the term has its ordinary meaning in section 422.-25(5). We hold that the trial court adopted the correct willfulness standard in the present case.
The court did not err in finding defendant guilty based on knowing and intentional violations of known legal duties.
AFFIRMED.
All Justices concur except CARTER, J., who dissents.