Is it legal to ask an employee about their health history?

My business is in Wisconsin.

I have to assume that you feel you have a legitimate reason for asking an employee to share his health history with you, but generally speaking, an employee’s health history is private and personal information. If your company requires a physical examination, the employee’s health history may be gathered as part of that examination by the medical facility doing the pre-employment physical, but even so, it should not be a matter of discussion between you and the employee. You really should only ask questions relating to the employee’s ability to do his/her bona fide job tasks.

If the employee is not doing his job, the behaviors should be assessed and the employee should be given a chance to remedy the problematic behavior(s). If you suspect any employees of having a health problem or disability that is affecting their ability to do the job, it would be advisable to deal with the observable behaviors that are affecting your perception of their competence in their role instead of delving into the employees' health history. If the employee volunteers information that he cannot do the job for medical reasons, ask for documentation from his physician regarding what job duties he can do, under what kind of duration, and so forth. Then, accommodate these restrictions if you can.