Does that make things clearer?

In the U.S., the executive branch of the government is responsible for enforcing the law, among other things. Any ambiguity in the law gives power to the enforcers since it gives them greater opportunity to use their individual judgment on whether a particular action has violated a law. The purpose of checks and balances in our three branch government is to prevent that kind of power from slipping from one branch (the judiciary) to another (the executive). The legislative branch is responsible for developing the laws, but ambiguous laws are routinely struck down by the judiciary for being too ambiguous. (Granted, this usually has more to do with laws being ambiguous in such a way that because citizens can't be sure if what they want to say violates the law they instead say nothing, and it is considered prior restraint of speech and therefore in violation of the first amendment.) The point of this paragraph, however, is that ambiguity in laws leads to trouble, and it is the responsibility of the legislative and judicial branches to avoid such ambiguity.

We, as citizens, are bound by law. We, as people, have some idea of what those laws should be based on our upbringing, philosophical beliefs, social environment, and religious beliefs (all of which overlap significantly). Where the overwhelming majority of us agree, the laws are easy; most everyone considers premeditated murder to be about the worst thing one can do, and thus first degree murder is illegal everywhere in the U.S. and generally carries a sentence of life in prison or even death. Where there is weaker agreement (especially historically), things are fuzzier; rape is considered by many to be as bad as first degree murder, but there are a lot of people out there who feel that the victims are somehow partly responsible, or even brought it on themselves, thus the penalty for rape varies from state to state and court to court.

What rape and murder laws have in common (and, indeed, the majority of the laws of the land) is that they are about protecting people from other people. This is one of the roles of the government. (Perhaps I'll talk about the necessary/useful/desirable roles of the government in another post some time, but I'll have to get all my reference ducks in a row first.) If one accepts that the law should protect people from one another, specific laws come down to an argument about one of two things: who counts as a person, and what actions should be protected against. The second issue is as worthy of debate as the first, but is a topic for another time.

Various groups of what we now consider people in various times and places have been considered non-people and, thus, have not been afforded protection from people. The more memorable examples include Jews (and others suspected of heresy) during the Spanish Inquisition, Jews under the Nazi regime, and slaves in the U.S. before the 13th amendment (and, arguably, their descendents up to and including the present). At present, there is even a vocal minority (e.g. PETA) who consider animals (or at least most mammals) to be people and thus deserving of the same protection under law.

So what makes someone a person? Is it that they are of the species homo sapiens? That seems to be a good definition, but it is insufficient if we ever encounter intelligent extraterrestrial life. Furthermore, it doesn't take into account our prevailing attitude that children are afforded different rights and protections from adults, as are the mentally incompetent. This, of course, is of those gray areas. The law, as developed by the legislature and interpreted by the judiciary, draws solid lines. Those solid lines are not intended to be "right" in some objective sense. In general, when a solid line is drawn in a gray area it is because there is no obvious right place to draw the line; the choice of where that line is drawn must not fall to the individual enforcers of the law (in the executive branch) but to the developers and interpreters of the law (legislative and judicial branches, respectively) so that it applies to everyone consistently. It is for this reason that the Roe v. Wade decision and subsequent legislation have drawn the line between "people protected from murder" and "non-people with no such protection" at birth.

The people of the United States do not agree on when a human life becomes a person. Pretty much everyone agrees that sperm and unfertilized eggs do not constitute a person, Pythonesque claims of "Every Sperm is Sacred" notwithstanding. Pretty much everyone agrees that when a child begins using language, he or she is a person. There are newborn infants left in dumpsters to die, abortions performed in all three trimesters, and emergency contraception (the morning after pill) throughout the U.S., indicating that there are people who believe that a fetus is a non-person from conception up to and beyond birth. At the same time, there are people who protest abortion clinics and demand that Roe v. Wade should be overturned so that any sort of artificial termination of a pregnancy, including emergency contraception and wounding a pregnant woman so that she loses the baby, should be considered murder. There is no strong agreement here, nor is there likely to be in the forseeable future. Without the presupposition of a divine answer, which is well outside the domain of the law, there can be no "right" line to draw.

Drawing the line at birth is a compromise. With the (comparitively) recent ban on "partial birth" abortions, the compromise has even been shifted. (Note that the legislation itself is flawed in that it is ambiguous about the breadth of what it actually bans, but that has been discussed thoroughly elsewhere.) One could argue that this shift is a move toward giving in to one group's opinions at the expense of another's, or one could argue that it is simply a balancing reaction to the weight of the pulls on either end of the spectrum. Nonetheless, the purpose of that solid line is not to protect babies from being murdered, nor to provide a woman with control over her own body, but to prevent the individual enforcers of the law from deciding on a case-by-case basis whether a woman is committing murder or legally discarding a part of her body.

What can be gained from understanding the discussion above? Those arguing vehemently to shift the line one way or the other, or even to prevent the line from being shifted, should be aware that the reason for the line is not to help or hurt their cause. Furthermore, the apparent hypocrisy of being against abortion and for capital punishment, or vice versa, is not hyposcrisy at all; it is just a difference of opinion on who counts as a person and who does not. Are blastocysts people? Some people say yes, some say no. Are murderers people? Some say yes, some say no. As righteous as many people feel about their opinions, the law must not be based on religious beliefs and, therefore, must draw arbitrary lines in gray areas that satisfy the majority of the people at best, and dissatisfy equally at worst.