It's generally believed that Karma can pass from one life to the next. In other words how you lived one life will affect how you live the next. Now the problem with this is that during your first incarnation you have no previous experiences to shape that first life and only by those around you will you learn from the experiences set forth. This means that you're nothing more than a child during your first incarnation however what you choose to do with the experiences you've had is by your own choosing. This is where freewill comes into play.
I spoke with a woman once who was supposedly "enlightened" and she told me a theory about reincarnation and how Karma affected a person's life. I'll use her example here.
When one man kills another
that man is destined to be killed
in his next incarnation
so he knows the harm he caused
by taking another man's life.
I disagreed with her and showed her the flaw in
this logic. If "A" was killed by "B" then in "B's" next
incarnation he is destined to be killed by "C." Does this
mean that "C" will be killed by "D" when in fact "C" was only
fulfilling a karmic contract? This can go on forever with
"D" being killed by "E" for killing "C" who killed "B" who
killed "A." There's not enough letters in the alphabet to
go on forever. With this logic all we'd be doing is
killing each other from one life to the next and that appears to
be what we're doing anyway. Again this means that freewill
does not exist and is only shaped from past experiences to
fulfill that Karmic Law. Is this what the Universe
intended for us? Where's the spirituality?