Your supervisor and mentor at work is getting ready to retire and you have been asked to speak at the farewell party.  A member of an ethnic minority, she frequently pokes fun at her own cultural background, so everyone at your workplace knows she is not offended by cultural humor even when the jokes are at her own expense.  In addition, you know your audience expects your speech to be humorous and lighthearted rather than a serious tribute.  You recall a joke your mentor recently made about her own culture and you consider including it in your speech recognition.  
Even if you are positive the joke would not offend your mentor, what other ethical considerations should you make when deciding to tell it?  Suppose you have the same ethnic and cultural background as your mentor, so the joke would be poking fun at you as well as her.  Does that affect whether it is ethical to include it?