You may have heard alarms that if we hold a national convention for proposing constitutional amendments the gathering would be an uncontrollable constitutional convention (“con-con”) that could propose anything at all.

The claim is called the “runaway scenario.” It has almost no basis in history or law. But it has long frightened Americans away from using the Constitution’s chief mechanism for bypassing Congress and curing our dysfunctional federal government.

The “runaway” specter has been raised by fringe elements on both the left and the right. It is a ghost that haunts the imagination of groups like the John Birch Society and Common Cause.

Now we have more information about how it was conjured up.

Last year, the Article V Information Center published my paper showing that confusion between an amendments convention and a constitutional convention first arose in the 20^th century. The paper further documents how, during the 1960s and 1970s, leading establishment liberals, such as Kennedy speechwriter Theodore Sorensen and Kennedy confidant Arthur Goldberg, capitalized on that confusion by raising the runaway specter.

The paper concluded that their plan was to scare people away from using the Constitution’s convention mechanism. Their goals were twofold. First, they wanted to protect from reversal by constitutional amendment several Supreme Court decisions that had proved highly controversial—among them Roe v. Wade, the case that legalized abortion nationwide. Second, they sought to block growing momentum for amendments imposing term limits and requiring a federal balanced budget.

Now the curator of the Article V Library has produced more evidence confirming these conclusions.

The Article V Library collects every state legislative resolution calling for an amendments convention. It also offers features for screening them by subject and for ascertaining which are still in effect.

Without prior knowledge of my own conclusions, Robert Biggerstaff, the library’s curator, conducted an n-gram search in Google Books to find out when the phrase “runaway convention” arose (now updated to 2008, the last year for which data are available). He discovered that the term was almost unknown until around 1960—when it suddenly became extraordinarily common. Usage rose to counter rising popular demand for constitutional amendments. In the 1990s, as momentum for amendments abated, so also did resort to the runaway scenario. Another n-gram searchshows that the abbreviation “con con,” widely used by convention opponents, also was invented around 1960.

Biggerstaff notes: “In the 1950’s and 60’s progressives actively sought change through courts when it was not possible through legislatures.  This was an express tactical choice to seek through judicial activism what was stymied by legislatures.”

However, their strategy had what he calls an “Achilles’ heel.” Supreme Court decisions can be—and several times have been—overturned by constitutional amendment. After the Supreme Court required states to reapportion their legislatures in the 1960s, for example, 33 of the necessary 34 state legislatures filed applications demanding a convention to propose an amendment reversing the court’s rulings.

“As a result,” Biggerstaff says, “it became important to neuter the Article V Amendment process—particularly to prevent triggering by convention applications—to protect progressive successes achieved in the courts.”

Biggerstaff concludes that this was why the runaway convention fiction suddenly emerged from nowhere during the 1960s. In his view, “generating unwarranted fear of the Article V convention process was a ploy introduced by progressives as a way to prevent states from countering progressives’ use of judicial activism.”

This article originally appeared in The Hill.