Lynching of black people is a very real and horrible event that occurred in this country. Joking or not saying what she said was wrong. People maybe too sensitive these days but in this instance she was flat out wrong. Ask her and I bet she agrees it was a stupid and uncalled for remark receiving just punishment.
http://www.umass.edu/complit/aclanet/ACLAText/USLynch.html
There are "2805 [documented] victims of lynch mobs killed between 1882 and 1930 in ten southern states. Although mobs murdered almost 300 white men and women, the vast majorityóalmost 2,500óof lynch victims were African-American. Of these black victims, 94 percent died in the hands of white lynch mobs. The scale of this carnage means that, on the average, a black man, woman, or child was murdered nearly once a week, every week, between 1882 and 1930 by a hate-driven white mob" (ix).