Plaintiff United States appeals the district court’s dismissal of 12 counts of a 28-count indictment. The district court held that the defendants lacked fair notice of the illegality of the tax avoidance schemes they developed and promoted, and that they accordingly could not have willfully violated the statute. We reverse and remand for trial.

BACKGROUND

Frank Forrester developed tax shelter programs designed to reduce taxpayers’ income tax liabilities. Under Forrester’s primary program, the “personal services contract,” taxpayers would “sell” their life services to Professional and Technical Services (PTS), an entity created by him, for one dollar per year. When the taxpayers received paychecks from their employers, they would endorse the checks and send them to PTS, which transferred the checks to International Dynamics, Inc. (IDI), another Forrester organization. IDI in turn transferred the funds to IDI Credit Union (IDICU), which would send the taxpayers “gift” checks equal to 90 to 92 percent of the taxpayers’ original paychecks. Some of these entities purported to be foreign trusts or corporations.

Forrester’s other tax scheme at issue here was the “9:1 tax shelter” under which taxpayers purchased “consulting services” from IDI. Taxpayers paid an allegedly deductible consulting fee to IDI, and IDI immediately sent the taxpayers an alleged tax-free reimbursement check less a ten percent fee. No consulting services were ever performed.

Defendants James Russell, Earhl Schooff, and Lawrence Richey were involved in the promotion and sale of these schemes. These three, along with Forrester, who is now deceased, were charged in a 28-count indictment with a variety of tax *573 fraud, mail fraud, and tax evasion violations.

On motion by the defendants, the district court dismissed twelve counts of the indictment, finding that under the reasoning of United States v. Dahlstrom, 713 F.2d 1423 (9th Cir.1983), cert. denied, 466 U.S. 980 , 104 S.Ct. 2363 , 80 L.Ed.2d 835 (1984), the defendants lacked fair notice of the illegality of the tax schemes until July 29, 1982 when the Eighth Circuit held, in a civil proceeding, that a “personal services contract”, similar to those involved in this case, was an illegal tax avoidance scheme. United States v. Landsberger, 692 F.2d 501 (8th Cir.1982). 1

The government appealed the dismissal of the twelve counts. The district court continued trial on the remaining counts, ruling that the time accruing during the pendency of the appeal would be deemed excludable delay under the Speedy Trial Act.

DISCUSSION

1. Appealability

The district court dismissed 12 of the 28 counts in the indictment, and continued trial on the remaining counts pending this appeal. To prosecute its appeal, the government “must show that it has the right to appeal and that the order appealed from comes within the terms of a statutory grant of appellate jurisdiction.” United States v. Dior, 671 F.2d 351, 354 (9th Cir. 1982). To satisfy the first prong, the government must be authorized to bring the appeal under 18 U.S.C. § 3731 . To satisfy the second prong, the decision being appealed generally must constitute a “final judgment” under 28 U.S.C. § 1291 . United States v. Martinez, 763 F.2d 1297, 1307 (11th Cir.1985). Despite the general application of § 1291’s finality requirement, “[sjection 3731 can, and does, make it lawful for the government to take certain appeals even though there is no final judgment.” Id. at 1308 n. 10. According to the Eleventh Circuit in Martinez , this “right to take an interlocutory appeal [must be] expressly provided in section 3731.” Id.

Title 18 U.S.C. § 3731 provides in relevant part: “In a criminal case an appeal by the United States shall lie to a court of appeals from a decision, judgment, or order of a district court dismissing an indictment ... as to any one or more counts.” Because the district court dismissed 12 of the 28 counts, the government is authorized to appeal under § 3731, thus satisfying the first prong. As to the second prong, the district court order is not a final judgment except as to Schooff because it does not dispose of the remaining 16 counts. 2 However, we have interpreted the quoted portion of § 3731 as expressly providing the right to take an interlocutory appeal in this situation. See United States v. Marubeni America Corp., 611 F.2d 763, 764-65 (9th Cir.1980) (court held that § 3731 supplied appellate jurisdiction where district court had dismissed portion of one count and had suspended pre-trial proceedings on remaining counts pending appeal; no discussion of § 1291’s finality requirement). Following Marubeni, we conclude that we have jurisdiction to hear the interlocutory appeal in the case at bar. 3

2. Standard of Review

The district court “assumed the truth of each material fact set forth in the indict *574 ment and, applying Dahlstrom , ruled that regardless of the evidence, the government would be unable to sustain its burden with respect to those counts which were dismissed.” The district court thus ruled as a matter of law, and we review this holding de novo.

3. Dahlstrom

The tax avoidance scheme at issue in Dahlstrom is described at 713 F.2d 1425 -26, and also in Zmuda v. Commissioner, 731 F.2d 1417, 1419 (9th Cir.1984). Zmuda was an appeal from a Tax Court judgment disallowing deductions and assessing civil penalties for use of a tax scheme virtually identical to the one at issue in the Dahlstrom criminal prosecution. At the heart of the scheme were three foreign trusts to be established individually by each taxpayer participant. Property or income was transferred to and among these trusts, and eventually transferred back to the taxpayer as a “gift.” Some of the transactions, including the “gift” to the taxpayer, were allegedly tax-free in part because of the foreign status of the trusts.

The Dahlstrom defendants were tried by a jury and convicted of conspiracy to defraud the United States and of aiding and abetting the preparation and presentation of fraudulent income tax returns. On appeal, the court noted that to convict a person for aiding and abetting the preparation and presentation of fraudulent income tax returns under 26 U.S.C. § 7206 (2), the government must prove the defendant acted willfully. 713 F.2d at 1426-27 . Under the statute, a “willful” act consists of “a ‘voluntary intentional violation of a known legal duty.’ ” Id. at 1427 (quoting United States v. Pomponio, 429 U.S. 10, 12 , 97 S.Ct. 22, 23 , 50 L.Ed.2d 12 (1976)). The court held that because “the legality of the tax shelter program advocated by the appellants in this case was completely unsettled by any clearly relevant precedent on the dates alleged in the indictment,” the defendants lacked fair notice of the illegality of their acts and thus lacked the requisite intent to violate the law. 713 F.2d at 1428 . The court accordingly reversed the judgments. Id. at 1429 .

4. Frank Forrester’s Tax Shelter Schemes

The heart of the primary Forrester tax shelter scheme was the personal services contract under which taxpayers sold their life services to PTS, one of the entities created by Forrester, for one dollar per year. The taxpayers were allegedly thereby obligated to transfer all paychecks to PTS. According to the indictment, the defendants assured the participants that the income was no longer taxable to them as individuals because PTS owned their paychecks.

As this court has recognized, “[t]he guiding principle in assignment of income cases is that income is taxed to the person or entity, which in fact controls the earning of income.” Johnson v. United States, 698 F.2d 372, 374 (9th Cir.1982). The Supreme Court first announced this rule in 1930 in Lucas v. Earl, 281 U.S. Ill, 114-15, 50 5. Ct. 241, 74 L.Ed. 731 (1930), and has often repeated it. See, e.g., United States v. Basye, 410 U.S. 441, 450 , 93 S.Ct. 1080, 1086 , 35 L.Ed.2d 412 (1973) (“The principle of Lucas v. Earl, that he who earns income may not avoid taxation through anticipatory arrangements no matter how clever or subtle, ... stands today as a cornerstone of our graduated income tax system.”); Commissioner v. Culbertson, 337 U.S. 733, 739-40 , 69 S.Ct. 1210, 1212 , 93 L.Ed. 1659 (1949) (court cites “the first principle of income taxation: that income must be taxed to him who earns it”).

The acts alleged in the indictment constitute violations of the statute because they contradict this “first principle” of tax law. Such anticipatory assignments of income have been recognized as ineffective to shift income for tax purposes for over fifty years. The defendants in this case had fair notice of the illegality of their scheme from its inception.

This fruit/tree distinction does not, however, save the defendants’ scheme. In Lucas , the Supreme Court held that “the tax could not be escaped by anticipatory arrangements and contracts, however skilfully devised to prevent the salary when paid from vesting even for a second in the man who earned it.” 281 U.S. at 114-15 , 50 S.Ct. at 241 . The indictment in the case at bar alleges that a taxpayer who signed a personal services contract “continued to work for his previous employer and receive paychecks in his own name.” The indictment further states that “the defendants orally assured these individuals that they did not have to turn over every paycheck to Professional and Technical Services. Instead, individuals who signed a ‘personal services contract’ had complete discretion over whether or not they turned their paychecks over to Professional and Technical Services.”

These allegations in the indictment indicate that participants in the scheme continued to “earn” their own salaries. The scheme is therefore illegal under Lucas . Calling the scheme an assignment of life services rather than an assignment of income does not change the nature of the underlying acts alleged in the indictment.

The fact that this scheme involved the use of purported foreign trust organizations, and that this particular scheme had not been ruled illegal until the Landsberger litigation, does not change the basic conclusion. Regardless of the entities through which taxpayers’ monies were funneled, the basic personal services contract remains an assignment of income that is ineffective for tax purposes. If it is clear beyond any doubt that a scheme is illegal under established principles of tax law, then participants have fair notice of its illegality even if no appellate court has explicitly so ruled. See United States v. Ingredient Technology Corp., 698 F.2d 88, 96 (2d Cir.) (“it is immaterial that ‘there is no litigated fact pattern precisely in point’ ”), cert. denied, 462 U.S. 1131 , 103 S.Ct. 3111 , 77 L.Ed.2d 1366 (1983). This case is thus distinguishable from Dahlstrom , where the court was “convinced that the legality of the tax shelter program advocated by the [defendants] ... was completely unsettled by any clearly relevant precedent on the dates alleged in the indictment.” 713 F.2d at 1428 . See United States v. Little, 753 F.2d 1420, 1433-34 (9th Cir.1984) (court distinguished Dahlstrom , noting that the law regarding retroactive partnership allocations was clear on the dates alleged in the indictment); United States v. Condo, 741 F.2d 238, 240 (9th Cir.1984) (court distinguished Dahlstrom , observing that the constitutionality of the taxing system was clear), cert. denied, 469 U.S. 1164 , 105 S.Ct. 924 , 83 L.Ed.2d 936 (1985).

The other Forrester tax scheme was the “9:1 tax shelter.” The illegality of this scheme was likewise clear beyond any doubt. “The incidence of taxation depends upon the substance of a transaction.” Commissioner v. Court Holding Co., 324 U.S. 331, 334 , 65 S.Ct. 707, 708 , 89 L.Ed. 981 (1945); see also Rickey v. Commissioner, 502 F.2d 748, 752 (9th Cir.1974). The indictment alleged that taxpayer participants contracted with IDI for the purchase of “consulting services,” paid a fee for the services, immediately received a “gift” from IDI equal to 90 percent of the fee paid, and never received any consulting services. They were told that the “fee” paid for the “consulting services” was tax deductible. This scheme lacks substance, and the defendants had fair notice of its illegality.

We conclude that assuming the truth of the allegations in the indictment, defendants were engaged in promoting tax schemes, the illegality of which they had fair notice. The district court erred in granting the defendants pre-trial motions for dismissal of 12 counts.

REVERSED and REMANDED.

. Landsberger involved only the "personal services contract,” and did not involve the "9:1 tax shelter.” The district court in the case at bar apparently concluded that pr^-Landsberger, the defendants lacked fair notice of the illegality of the “9:1 tax shelter” as well, because the district court dismissed at least one count involving only the "9:1 tax shelter.”

. We note that defendant Schooff was charged only in count I, which was dismissed. The district court’s order is therefore final as to Schooff. The interlocutory appeal issue arises only as to defendants Russell and Richey.

. At the end of its Order, the district court stated: "To the extent that this Court has any authority to entertain the government’s motion for leave to take an interlocutory appeal, the same is GRANTED." This statement has no effect. There is no provision for district court certification of interlocutory criminal appeals analogous to 28 U.S.C. § 1292 (b) regarding interlocutory civil appeals.