Karma does not exist. There are lots of good things that happen to bad people, and bad things that happen to good people. While it is true that if you're a dick people will be a dick back to you, and if you're nice people might be nice back to you, that's not so much karma as it is basic psychology. If the universe had a built-in justice-creating force like karma or a deity who gives two shits about us, there would be no infant mortality, no 9/11, no Hurricane Katrina, no gigantic tsunamis, no world hunger, and no AIDS epidemic.