Unless you're the director on the movie, or putting up the money for the movie, you really don't have a lot of control.
In the case of abortion, one pits the life of the fetus against the interests of the pregnant woman.
Murderers will try to recall the sequence of events, they will remember exactly what they did just before and just after. But they can never remember the actual moment of killing. This is why they will always leave a clue.