Here's a comment on the article I found interesting:

Karma is related to thought, intention, and action. So, if a person commits a crime once, there's probably not a whole lot of karma there. If a person lives a life of crime, then there is a whole lot of karma there. If you live a life in which you were raised in neglect and poverty, and turned to a life of crime because it was easier, then there's a pattern of behavior involving intention, thought, and action related to crime - that pattern is karma (Karma is not "do a good thing, and good will come back to you/ do a bad thing, bad things will happen to you" - there is an element of that, but it's much more complicated). In any case, many people extract themselves from a life of crime. How? They decide to change their lives - in this way, they are breaking a karmic pattern. There are many ways to do it, but one way to break a karmic pattern is to meditate, see clearly one's thoughts and actions, and in the stillness, let go of negative thoughts that might keep one in a certain (in this case, a life of crime) karmic cycle. But again, intention is involved: if a person doesn't have an intention to change, no amount of meditation will help. Shorter answer: yes, Buddhism (not me) says that a person can meditate on their karmic situation, and seeing it clearly, they can let go, and thus, at least to some degree, change their karma with present thought, intention, and action.