http://www.religioustolerance.org/abo_when7.htm

It provides a good overview of how each state describes a fetus, and how they outline criminal charges for fetal death. It's something you can use when someone starts using the Laci Peterson case and the Unborn Victims of Violence Act to make a case against abortion. The Peterson case was under state jurisdiction (California), while the UVVA is a federal law that applies only in certain situations.