There was some black people hanging around the park yesterday until the cops pulled them down.
This punchline of this joke seems to be about black people being killed. I'm not sure this is something to laugh at.
Hahaha relax, the joke is on them as they dont have a right to spend time in the park anyway. Chill.
Black people being lynched is a historical tragedy and it isn't something that is appropriate to joke about in polite company since it trivializes the victims of lynching. It would be good to avoid such jokes as people will think badly of you for telling them and will not want to spend any time around you. Instead of joking about the victims of such tragedies it would better to find lighter subjects to joke about so people will consider you to be pleasant and gregarious.