The legal issues are obviously regional based, but most of them would be universal.

Off the top of my head.

* Ensure that your workplace is a physically safe place. ie enough lighting, correct furnishing etc.

* The data you are working with is protected adequately. ie A separate room with lockable door and window.

* The infrastructure is adequate. ie internet, electricity, water and toileting.

* Insurable if something goes wrong.

* How your work time is measured. This is particular important if your industry is covered by union rules.

In the USA the Department of OHSA specifically says that it (and the employer) don't bear responsibility for a home based work site. They won't do site inspections and the best they can do is give tips to the worker and have the worker complete a self-assessment. Overseas this is viewed very differently. e.g. in Australia and UK the employer is responsible for worker safety even if they are working from home.

https://www.osha.gov/enforcement/directives/cpl-02-00-125

"OSHA will not conduct inspections of employees' home offices.

OSHA will not hold employers liable for employees' home offices, and does not expect employers to inspect the home offices of their employees.

If OSHA receives a complaint about a home office, the complainant will be advised of OSHA's policy. If an employee makes a specific request, OSHA may informally let employers know of complaints about home office conditions, but will not follow-up with the employer or employee."

I assume one potential issue is the question of where people are actually working from. Although in my experience, most people have an official location even if they’re rarely there. It may differ with consultants etc. who may be working from a customer site for months.

We were told that for tax purposes, employees are only allowed to work in states/countries that already have an established office. My company has offices all over the place so it's not particularly restrictive but still a strict limit from working _anywhere_.

I've definitely encountered cases where a company didn't have an office in states where employees were located. In some of these cases, employees may have been de facto remote but still technically had an office at the company's location. Others though an employee was clearly remote in a different state.

What I can't speak to is what sort of legal presence the company set up in the remote employee state of residence. (An office may not be needed but some sort of legal paperwork may be.)

Data protection and worker's comp in my experience.

Insurance when the employee is not here I guess