he filmmaker Ava DuVernay’s 2016 documentary13th made a powerful historical claim pithily encapsulated in its subtitle: “From slave to criminal in one amendment.” The argument goes like this: The 13th Amendment’s so-called exception clause, which outlawed slavery “except as a punishment for crime whereof the party shall be duly convicted,” effectively converted race-based slavery into race-based incarceration. That thesis has fascinated amateur history buffs, motivated activists, and given rhetorical ammunition to politicians like Bernie Sanders, who explained in an essay for Medium that, “due to an extreme shortage of labor caused by the emancipation of slaves, former Confederate states exploited the legalization of penal labor by incarcerating newly freed Black people.”

The problem, according to the Howard University historian Daryl Michael Scott, is that it’s just not true. Scott, in an essay in Liberties, coins the term “thirteentherism” to describe what he says is a fundamental misconstrual of the historical record. “In keeping with our era,” Scott writes, “bad history and worse social science have replaced truth as the intellectual underpinning for a great deal of thinking about social change.” I talked with Scott recently about propaganda, myth-making, student protests, and Facebook.

As you explain, the theory that the 13th Amendment allowed for the functional re-enslavement of freed Blacks emerged not from professional scholars but from the incarcerated activist Lee Wood, in the 1960s. It was a powerful tool for consciousness-raising in that context.

I had no idea where it had come from initially. Within the academy, I traced it back to Angela Davis. She didn’t make that big a deal of it — it was a passing comment. A little hyperbole in an essay usually means nothing.

When I started going back and searching, I learned about Lee Wood, the guy who was in prison in California and said he discovered this. He had an epiphany when he read the 13th Amendment among a group of prisoners.

You could understand that. The claim by prisoners is, from the very beginning, a weapon in the struggle to change their world.

But the academics, the people who are paid for their thinking and research, are going along with the movement. They don’t seem to have a critical capacity to say: We see what you’re doing, but we differ with you.