"law marches in the direction of ever improving it's fit to society"

Right, we're all in agreement here. Law should conform to society, society need not conform to law. When the law is wrong, we can resist it, and when the law is absent, we can replace it.

Why should the law evolve to be more just? If anything, wouldn't the laws that were most fair be the ones that due to their age in spite of history's blows indicates preferential selection, and that age of the law may correlate to the relatively simplicity of its authoring government and hence maybe fewer externalities. We now live in a period of perennial voter disenfranchisement, and it seems that the civil rights movement will not have the lasting stopping power it was perceived to wield to cement incremental progress in our society. I think that recent legislation, although almost never as surely heinous as chattel slavery or slaughter of Native Americans or racial quotas etc., that there is a difference between the 'what we think is worth keeping' and the 'what we can expect to be exasperatingly legislated in the near future'