Can an employer wipe an employee's BYOD device (e.g. the employee's personal phone)?

[MarcoJ]

Many workplaces allow employees to use their own personal mobile phones for work purposes, aka Bring Your Own Device (BYOD), which employees may actually prefer because it is easier than carrying two phones, i.e. a personal phone and a separate work phone. The phone is then enrolled into a Mobile Device Management (MDM) system, such as Microsoft Intune, that allows the employer to manage and control the device. This in itself is sensible, because when the employee leaves the employment, the employer will want to be able to remotely remove any corporate data from the employee's personal device. However, I have recently learned that in this scenario the MDM can also be used to perform a 'factory reset' on the mobile device thus erasing all data, including the employee's personal data. I am concerned about the legality of such a scenario. Firstly, can the employer ask employees to enrol their personal device, without explicitly explaining to them that by enrolling they are also making it possible for the employer to delete their personal data from the device? Then, if making the employee aware, would it be legal to have the employee sign some sort of waiver (if they agree to it, obviously)? To clarify, I am not suggesting that employers may act maliciously, just wondering how to approach this issue from the legal perspective. Also keeping in mind that mistakes can happen, and it is always possible that a 'remote wipe' command will be sent to an employee's mobile phone due to an operator error or system fault etc. I am wondering if anyone has any input regarding this issue - many thanks.