I know that Darwinists and positivists were on the march in the late 19th century and had a sizable audience among the mega-industrialists and the old-money elites.
Their invasion of the legal field would have been an invasion indeed, since the country was far more given to self-identifying as a "Christian country," and corresponding to that, the law was understood to express a Christian metaphysics of mankind in the garden of good and evil.
Then, while the Taylorists were applying their mechanistic "weird science" to the new workplace of idealized human drones, the legal innovators of the time were disembodying the law from its hard-earned structural and philosophical underpinnings while they professed to admire it as a system of postulates that "worked well" (at least for those in power, whom Holmes regarded as the law's true source anyway).
Having said all that, given the Natural Law's metaphysics of good, evil, and the nature of man, I keep thinking we need a revival of Natural Law theory to rescue the law from the many soulless clinicians and fiery-minded revolutionists who rank among its custodians.
An aside: have you ever considered that those who mocked common laws as arbitrary (and so needing to be abandoned) could only offer in their place forms of laws that were and could only be by their very nature Arbitrary to their core?
Whatever their failings different common laws were generally received, they had a character unique to themselves that could only be altered by the Sovereign.
One of the brilliant achievements of our founding was to retain English Common Law (the free system of law mentioned in the DoI) but removed from the central government the full Sovereignty, as the Constitution is merely an enabling act and not what the Court has arrogated it to become.
A Law, whatever it’s strengths or defects, that is a particular thing and difficult to change except by extraordinary means (the amendment process) was an astounding achievement in (little “s”) secular governance.
At its inception ours was a nation where the government needed specific, enumerated permission to do anything and the people didn’t.
Now We the People need an endless array of licenses from some government to do anything while it does as the political elites please.
That transformation was not progress.