You might find that some of your employees would prefer to work on their Mac verses the PC you’ve provided, or as a supplement device. Should you tell them yes and save yourself some money on new PCs? Yes, provided you follow a few simple guidelines.
First and foremost, you need a policy outlined in an agreement the employee signs detailing what the responsibilities and rights are for them and for you. For starters, you should make it clear that the company retains ownership of the DATA on the device, even though the employee owns the actual device. All employers should have a confidentiality agreement in place with their employees anyway, but if your confidential data is on their device, you want to make sure you can retrieve it and/or delete it from their device.
Second, you need to make sure the employee takes care to NOT disable anti-virus software or to download viruses. Since the employee owns the device, they will (most likely) take it home and use it for personal web browsing. If their after hours activities invites viruses on their device, your data can be stolen or the hacker can use their device as an access point to your entire network. Can this happen with work-issued PCs? Yes, but people tend to be more liberal with their own devices than a work laptop or workstation.
You should also clarify that you have the right to “govern” the data on the device, which means you might also be able to access personal information of theirs. And finally, your agreement must clearly define what happens if the employee leaves or is terminated. They may have downloaded software that you (the company) has paid for. In that case, you’ll need to figure out a way to retrieve the license from their device. We highly recommend you get with a qualified HR professional or attorney regarding these matters to make sure you are complying with all state and federal laws in this manner. Otherwise, you could end up with an ugly lawsuit over the matter.