In Bell Atlantic v. Twombly (2007) and Ashcroft v. Iqbal (2009), the Supreme Court gave trial courts more latitude to dismiss a lawsuit at a very early stage, before the parties have had a chance to engage in discovery (the often lengthy and expensive fact-finding stage of civil litigation), if judges think the suit is not founded on “plausible” allegations of wrongdoing.

There’s a rich, angry debate about the effect the decisions will have on dismissal rates of meritorious suits in lower courts. But the consensus among academics seems to be that both decisions will trigger a sea-change in lower court practice—one deeply unfavorable to plaintiffs.

We won’t know the real effect of these decisions for many years to come. But a 2007 study by the Federal Judicial Center on the effect of a trio of similarly controversial 1986 Supreme Court decisions (known as the “Celotex trilogy”) raises questions about dire claims that Twombly or Iqbal will dramatically change lower court practice.

The debate over the Celotex trilogy in the 1980s is eerily similar to today’s debate over Twombly and Iqbal. Responding to concerns that juries award arbitrarily large judgments against corporate defendants, the Celotex trilogy gave lower courts more latitude to grant summary judgment—that is, to toss lawsuits at the end of discovery, before a case gets to a jury, when the judge thinks there is insufficient evidence to justify a jury trial. Many academics complained that the cases would result in a radical sea change in lower court practice—one that benefited corporate defendants at the expense of plaintiffs.

The FJC’s 2007 study is the most comprehensive study of the effect of the decisions to date. Based on data drawn from 15,000 docket sheets in randomly sampled terminated cases in six district courts, the FJC found (as expected) that, before and after the trilogy, summary judgment filing and disposition rates vary significantly from circuit to circuit and between types of cases. After controlling for differences in filing rates across circuits and for changes over time in the types of cases filed, the authors found that “the likelihood that a case contained one or more motions for summary judgment increased before the Supreme Court trilogy, from approximately 12% in 1975 to 17% in 1986, and has remained fairly steady, at approximately 19% since that time.” Moreover, between 1975 and 2000, “no statistically significant changes over time were found in the outcome of defendants’ or plaintiffs’ summary judgment motions, after controlling for differences across courts and types of cases.” Indeed, despite anecdotal claims that Celotex prompted a significant increase in summary judgment in civil rights cases, the authors found “no evidence that the likelihood of a summary judgment motion or termination by summary judgment has increased” in civil rights cases since 1986.

It’s easy to overstate the FJC’s findings. (The data tell us nothing about the quality of summary judgment decisions before or after Celotex, and shed no light on disposition rates at a micro-level, i.e. in product liability actions, as opposed to other tort actions, or Title VII actions, as opposed to other civil rights actions, for example.) The study nonetheless lends some plausibility to the view that Celotex was less a catalyst for change than a ratification of preexisting lower court practice that had evolved largely in spite of the Supreme Court and which the Court was, and is, largely powerless to control.

It’s easy to think of reasons why trial courts’ summary judgment practice might evolve independently of the Supreme Court. A surprisingly large number of trial court decisions, including grants of partial summary judgment, are not immediately appealable—and the pervasiveness of settlement means many of these decisions are never appealed. Intermediate appellate courts, moreover, affirm trial court decisions at an incredibly high rate. And the Supreme Court, which takes only about 80 appeals a year, has dramatically limited capacity to police the innumerable summary judgment dispositions made daily throughout the federal court system. The upshot is that trial courts, as a practical matter, have long had wide discretion to decide even pivotal motions, like summary judgment, with relatively light appellate oversight.

Are Twombly and Iqbal a replay of the Celotex trilogy? Only time will tell. But what we know, to date, about the Celotex trilogy suggests that, whatever you think about Twombly or Iqbal, strong claims about the influence of either decision may well overstate the Supreme Court’s power and influence over trial court practice.