Most events that lead to the termination of an employee are going to occur at work or relate to the employee’s job. But can you fire an employee for off-duty conduct that doesn’t directly relate to his job? The answer is typically yes, as this high level executive who slapped a toddler on an airplane found out. http://www.local8now.com/home/headlines/Man-charged-with-slapping-toddler-now-out-of-a-job-191661441.html?llsms=92311&c=y
If the employee is at-will, the termination will be much easier. In that situation you don’t have to have any reason to fire the employee. But to put employees on notice that their off-duty conduct might come back to bite them, I recommend puttting something in your Rules of Conduct to address the possibility. Something like ” Any conduct that may discredit you, the company, or fellow employees” should work.
If the employee has an employment contract and can only be terminated for “cause” make sure cause is defined to include the “discredit” lnaguage stated above, as well as things such as any act of dishonesty, fraud or theft, and a conviction or plea of guilty or no contest to any crime (other than speeding).