Actually, our individual omnipresent soul can be understood to be divided into 10 different souls, of which one is affected by pitra dosha,...... like wise - similarly one part of it is affected by the fine worried thought ejaculated (occured)/(desire expressed) during thoughtlessness i.e. death moments.
These combined forces decides one's next set of ...
Let's say Somu kills Kumar.
Did Kumar deserve it? Yes. Why? Shastras tell us Law of Karma decides your birth & death. So Kumar deserved to die exactly at that time in that manner.
So, can we let Somu go free? No. Why not? Because Somu committed a crime.
How can it be a crime if Kumar deserved it? Because Shastras tell us that murder is a crime.