As with any labor law or legal liability issue, there are probably more ways to trip up than you ever imagined. This article at Faegre.com, which I found via George's Employment Blawg, has a nice summary of key issues in five categories.
Because the vast majority of our employees are over 70, and a number of them have disabilities, we have to be very careful in hiring. Many of our jobs can be physically challenging, and dangerous to perform with some disabilities, so we have to take care to make sure an employee understands the work and that we mutually agree they can do it safely.
One related area that I am not sure has been tested regards our corporate insurers. Increasingly, insurers, particularly for our corporate vehicle policies, are refusing to insure over-70 drivers without some kind of letter from a doctor that they are capable of driving safely. As you can imagine, doctors face liability if they put in writing the employee can drive safely (so the doctor might be liable if there is an accident) or if they write that the employee can't drive safely (so the doctor might be liable for effectively denying the employee insurance, or even a job). As a result, doctors are reluctant to produce such letters.
It has not come up yet, but what happens if one of my employees is uninsurable for driving, and driving the company vehicle is an essential part of their job? Do I face an ADA case for discharging them? What choice would I have in that case?
We also have very severe challenges with off-duty behavior. Most all of our employees live on the job site (i.e. the campground managers live in the campground). So, off-duty behavior occurs on the job site. Until I had this company, I always said that I did not care what an employee did on her own hours at home - but now, what happens on the employee's own time occurs in front of my customers.
We continue to walk a fine line on this. To date, we have told employees that even if they are not on the clock, if they are wearing our uniform or verbally representing themself as a company employee, they are subject to on-the-job behavior rules. Once the uniform is off and they are just "Joe", and not "the manager", they are free to do as they please, though they are still bound both by federal and state laws as well as campground rules.