No such thing as Karma as explained in religion:
kar·ma (kärm)
n.
1. Hinduism & Buddhism The total effect of a person's actions and conduct during the successive phases of the person's existence, regarded as determining the person's destiny.
There is a such thing as improving or worsening relations with people by exhibiting preferred or unpreferred behavior, who are the only agents to observe and interpret your actions in a similar fashion (and this is the same reason why the original concept of karma is impossible; no divine judge, or afterlife for that matter, can be known of.) When you treat people in a way they wish to be treated, they typically return the behavior in kind. OTOH, if you treat people in a manner they do not like, they will also return this behavior, whether an exact replica or simple avoidance.
The universe ain't gonna punish you if you kill a guy. You don't have an increased chance of being struck by thunder or getting cancer for the act alone. You do, however, have to deal with the ramifications of having ostracized yourself from the rest of common society, the direct effects of which can easily lead you to an early grave or a lesser life.
Likewise, the universe ain't gonna reward you if you donate to charity. You're not going to grow back any missing limbs or braincells, you're not going to get an increased chance of finding money. However, people respond favorably to these things, they're more willing to help you when in need and more happy to be around you, which can lead to greater opportunities in life.
If there existed a real force like karma, we all know politicians and corporate heads would be in far worse spots than they are now, but they're not; this is because "karma" as described here is subject to the human experience, and so long as people agree that the actions which take place to make those people rich are legitimate, they'll continue to get all that "good karma"; they will never get what's coming to them without human action or accident of nature, and accidents aren't subject to karma.