Do Christian Reconstructionists “argue from silence” when they say that civil government should not presume upon powers unless such powers are explicitly granted to them in scripture? 

If I’m understanding him correctly, in this article Peter Leithart claims that reconstructionists “argue from silence” that civil governments are not granted authority unless “explicitly” granted. Contra reconstructionists, Leithart argues that civil governments are not granted authority to punish unless *generally* granted.

In agreement with reconstructionists, Leithart agrees that authority which is not granted to the civil government is forbidden, he just gives a wider berth for what is granted. I’m not sure how he doesn’t see that his subsequent accusations that the reconstructionists improperly argue from silence apply back on him. Whether specific or abstract, it’s still an “argument from silence” in some sense. What’s good for the goose etc.

But even on the claim that reconstructionists only affirm authority that is “explicitly” granted, reconstructionists don’t woodenly argue that “arson” (though not named as a specific crime in scripture), cannot fall under the judicial category of theft. So it’s not true that reconstructionists require “explicit” justification for every conceivable law permutation. The limiting factor for what prevents things like the legitimacy of public schools, welfare programs, and the prison complex (entities Leithart mentions in the article) are indeed the *categorical* absence of the God granting authority to the civil magistrate to manage these entities. Leithart casually mentions that he’s against the legitimacy of these institutions for “other reasons”, but unhelpfully, he doesn’t say what those reasons are.

In the end, it seems the only two options are civil authority being granted unless forbidden, or forbidden unless granted. Why is it assumed that advocacy of the former is also not an argument from silence? Moreover, with the former, there is no consistent limiting device that I know of that would definitively preclude the creation of everything from complete communism to an Orwellian police state.

In any case, whether someone claims the former or the latter, if we untether the authority of the civil magistrate from the categorical imperatives of scripture, someone can always appeal to “general principles” of “justice”, “love”, “holiness” to give them an excuse to do what seems right in their own eyes with a “biblical” bow on top. A China-like one child policy, the Green New Deal, government healthcare, it’s all on the table. 

Finally, what about if God actually is silent on this?  When God is “silent”, does not it make more sense to avoid presumptuous coercive action? In this sense, I don’t think all “arguments from silence” are bad. Presumptuousness is never a good thing.

They made kings, but not through me. They set up princes, but I knew it not. With their silver and gold they made idols for their own destruction.
Hosea 8:4

It makes far more sense that the civil magistrate who thinks he has carte blanche authority to regulate whatever activity he wants (unless forbidden) must make the case that he has biblical license to do so. I would think Leithart would agree with this, so in the end, I’m not sure he’s provided any consistent alternative against reconstructionists.