The most important laws we abide by are laws of behavior, not laws of nature, though hopefully the two sets of laws are consistent.

Laws of behavior in this country largely come from the legislatures that make them and the courts that verify them, and ultimately the supreme court.

Most of these laws are very practical, like not going through red lights. Many of them make society more efficient, and some less so. Many of them infringe on our personal lives, sometimes to the point that we protest. Yet almost all of these laws have not been verified by science. We believe in them and obey them because it practical to do so, not because they are scientific (or religious.)

The most important laws of religion are laws of behavior. For the most part they are outside the realm of science. But in some cases they conflict with science. Abortion is a good example. It is part of established medical practice, and medicine is a science. In the past, the medical field has defined life from birth, not conception. Now it seems to be more like the end of the first trimester. Law still seems to use birth.

I have always advocated defining the beginning of life consistent with defining when a person is dead. So now dead means brain dead. And so life should mean brain waves. These are all measurable. Yet the definition of life and death is still somewhat arbitrary. You cannot do an experiment to tell if a person is alive or dead without first defining what life is. Our data is from people in comas, and under what conditions they can come back to life. Those conditions are not exact, some person to person variations, but they are quantifiable. And they can be used to define life. But the choice to do it that way is still arbitrary.

The Christian religion defines life on the basis of the soul and the assumption that the soul comes into existence when the sperm fertilizes the egg. But Christianity is alone among religions in denying the prior existence of the soul. If we assume for argument the existence of the soul and reincarnation, then the questions change dramatically. When does the prior existing soul enter the body. Is it OK to kill the body before this time. Afterall it is supposedly impossible to kill the soul. Then religion could argue that it's always OK to kill the body as the soul always survives.

Fortunately western religion has put saving life above every other religious law. This has come to influence medical practice more than any other religious law, and even influence the conduct of war, at least where our soldiers are concerned.

This is basing ethics on life rather than soul. Life can be detected and therefore western society is much more consistent with science than other societies where the bases of ethics is on something that cannot be measured.

So I advocate basing laws on science as much as possible. But in this regard science has limitations, and it's important to recognize them, rather than having blind faith in science. I am not claiming that you do. But far too many do. For example, science cannot say what the best political system is. History does a better job at that than science.