Indeed, even with regard to an apparent contract, which is not absolute but relative (i.e., there is an external appearance of a certain contract behind which a different arrangement between the parties is hidden), there is a dispute in case law as to whether the court is entitled to enforce the hidden contract between the parties, i.e., the real agreement between them, despite the nullity of the apparent contract (Civil Appeal 10137/05 Eliyahu Lieberman v. Tadepi in a Tax Appeal (August 14, 2005, Paragraph 16). However, in other municipal applications 630/78 Biton v. Mizrahi, IsrSC 33(2) 576, 581 (1979)), it was ruled by a majority opinion that an agreement in which the parties specify a sum of consideration lower than that which was actually agreed upon, constitutes an illegal contract and not an ostensible contract (the Honorable Justices A. Vitkon and D. Bechor, against the dissenting opinion of the Honorable Justice A. Barak). The Honorable Justice Barak held in the same case in a minority opinion that such a contract should be regarded as a contract for the sake of appearance, and that when it comes to a relative appearance (relative simulation), as opposed to an absolute appearance, the hidden agreement between the parties behind the apparent agreement should be enforced (see more: Civil Appeal 6667/10 Galit Halevi Bar Tendler v. Dror Kuznitzky (September 12, 2012) - paragraph 31 of the judgment of the Honorable Justice Amit. Hereinafter: "The Tendler Case"; T.A. (Tel Aviv District) 2641/05 Michael Amran v. Estate of the late Zechariah Aryeh (March 26, 2012); T.A. (Haifa District) 62337-05-19 Yosef Hujairat et al. v. Ahmad Hujairat et al. (September 7, 2023)).
In our case, therefore, the contracts entered into between the plaintiffs and defendant 4 are illegal and not prima facie contracts. The illegality thereof was expressed in the reduction of the amount of consideration in order to defraud the tax authorities and enrich the coffers of defendant 4 and the transfer of the Goren hearing venue, and there was no additional purpose other than the aforesaid. These are illegal contracts, even if the illegality is incidental to the contracts. Therefore, these contracts are liable to be null and void according to section 30 of the Contracts Law. In such a case, prima facie, against the return of the sums received by defendant 4 (and the transfer of the Goren hearing venue) to the plaintiffs, the plaintiffs on the other hand are obligated to recover after cancellation in accordance with section 21 of the Contracts Law and section 9(a) of the Contracts Law (Remedies for Breach of Contract), 5731-1970). The conceptual basis for the duty of restitution is to prevent the unlawful enrichment of one party at the expense of the other, since upon the cancellation of the contract, the legal basis for holding the transferred resources is omitted (the Prosperi case; Civil Appeal 5267/03 Adv. Sigal Faraj-Gashouri v. Yael Meital (January 18, 2005) (hereinafter: "The Sigal Farag-Geshuri Case").