I don't know how you could prove that it isn't murder. It seems clear to me that since most of us agree that at a certain point in the fetus' development, there is life. After all, you can't get an abortion when your 8 months pregnant. I do not understand why they draw the line at that? If after a certain number of weeks an abortion is illegal, why is there an arbitrary date, I think that as both the parents of the fetus are human, and the necessary things for life are developing as the sperm fertilizes the egg, that fetus is alive. When Roe v Wade in the US and the abortion act of 1967 in the UK were passed they never proved this theory wrong, they only said it was a "woman's right to choose".