Is a Muslim sinful if he requests a transfer from a department headed by a Muslim to another department headed by a non-Muslim, thereby willingly entering under the authority of a disbeliever?

The headship of a department or similar governmental positions are not considered public offices whose assumption by non-Muslims is forbidden, unless it involves extending authority over a Muslim or humiliating them, or delegating authority for the employee's personal judgment without a higher reference point. Some scholars differentiate between positions of delegated authority, which require Islam, and executive positions, which do not. Dr. Abdullah Al-Tareeqi mentioned in his dissertation that the default is the impermissibility of appointing dhimmis, and this prohibition is confirmed for religious and public positions. As for ordinary positions that do not involve extending authority over Muslims, it is permissible to assign them to a dhimmi when there is a need. Accordingly, it is permissible for a Muslim employee to work in a department headed by a non-Muslim, unless it involves humiliation or denigration of their religion, although it is preferable for a Muslim to be headed by a Muslim.