Is it permissible to present to the court signed promissory notes for the receipt of the other half of the salary, claiming that the employee received his full salary, after the employee and the employer had agreed that the employee would not work for a certain period in exchange for receiving only half of his salary?

If the regulations require work during the summer vacation, it is not permissible for the manager and the employee to agree to violate these regulations. It is also not permissible for the employee to take any part of the salary in exchange for work not performed. It is forbidden for the employee to demand the remainder of the salary, because it was not lawful for him to take half of it in the first place, and it is not permissible to claim that he took the full salary due to the falsehood involved in such a claim. A judge's ruling does not make the unlawful lawful, as the Prophet, peace and blessings be upon him, said: "Indeed, I am a human being, and you bring your disputes to me. Perhaps some of you are more eloquent in presenting their arguments than others, so I may rule in their favor based on what I hear. So, whoever I rule for, taking something from his brother's right, let him not take it, for I am only cutting off for him a piece of Hellfire."