New York Times

WASHINGTON — Six years ago this week, the Supreme Court transformed civil litigation in the federal courts, making it much easier for judges to dismiss cases soon after they are filed.

The decision, Ashcroft v. Iqbal, may be the most consequential ruling in Chief Justice John G. Roberts Jr.’s 10-year tenure.

It has been cited in more than 85,000 lower-court decisions. But lawyers and law professors continue to differ about its practical effects, which are harder to measure than one may think. The latest and probably most thorough in a long series of studies, to be published in the Virginia Law Review, concluded that the decision had hit the powerless the hardest.

Before Iqbal, cases brought by individuals represented by lawyers were dismissed 42 percent of the time. After Iqbal, the rate was 59 percent. For corporate plaintiffs, the rates of dismissal stayed basically flat, edging up to 38 percent from 37 percent.

Employment discrimination and civil rights cases have become particularly vulnerable to early dismissal, the study found.

“Although one might expect individuals to fare worse than organizations as a general matter in our legal system,” the study said, the Iqbal decision “has increased the extent of the inequality.”

Before the decision, all plaintiffs had to do to start a lawsuit was to file whatthe rules of civil procedure call “a short and plain statement of the claim” in a document called a complaint. After filing such a bare-bones and often formulaic complaint, plaintiffs would be entitled to force defendants to open their files and submit to questioning under oath.

Since the Iqbal decision, which was decided by a 5-to-4 vote, plaintiffs must set out concrete facts at the outset. The decision then requires judges to scrutinize complaints closely and to dismiss ones that strike them as implausible based on their gut instincts or, as Justice Anthony M. Kennedyput it for the majority, on their “judicial experience and common sense.”

The new standard is sometimes called “plausibility pleading.” Soon after it was announced, Justice Ruth Bader Ginsburg, who had dissented, told a group of judges that it had “messed up the federal rules” governing civil litigation.

A couple of years later, a federal appeals court judge said the new standard might have required dismissal of the terse complaint in Brown v. Board of Education, the one that led to the Supreme Court’s landmark 1954 school desegregation decision.

The new study was prepared by Alexander A. Reinert, a professor atCardozo Law School at Yeshiva University in New York. He represented the losing side in the Iqbal case, which may explain his dark fascination with its aftermath.

“In a way,” he said in an interview, “I would love it if all the empirical data was saying that Iqbal had no impact whatever. It would make me feel better.”

Professor Reinert’s client was Javaid Iqbal, a Pakistani Muslim who was working as a cable television installer on Long Island when he was swept up on immigration charges in the aftermath of the Sept. 11 attacks. The Supreme Court ruled that he could not sue two Bush administration officials — John Ashcroft, who was the attorney general, and Robert S. Mueller III, the F.B.I. director — for what he said were humiliating searches and vicious beatings during his detention.

Justice Kennedy said Mr. Iqbal’s complaint had not cleared the plausibility bar. All it suggested, Justice Kennedy wrote, “is that the nation’s top law enforcement officers, in the aftermath of a devastating terrorist attack, sought to keep suspected terrorists in the most secure conditions available.”

Whatever else might be said about Mr. Iqbal’s case, it was unusual and so not an obvious vehicle for rewriting the rules for all kinds of routine civil litigation.

Lawyers representing defendants have embraced the decision. To hear them tell it, plaintiffs used to be able to gain unfair settlement leverage simply by filing a lawsuit.

They have a point. Based on nothing more than general allegations, plaintiffs could subject defendants to the expenses and inconvenience of the pretrial fact-finding process called discovery. And the American legal system usually requires each side to pay its own lawyers, no matter who wins.

On the other hand, information about wrongdoing is often secret, and plaintiffs need discovery to unearth the facts about, say, dangerous products or discriminatory practices.

“If we kick more cases out prematurely,” Professor Reinert said, “we are potentially losing cases that could play an important role not only in the lives of plaintiffs but also in the law and society.”

Earlier studies of the effect of Iqbal, based on judicial opinions in legal databases, found a marked increase in dismissals in its wake. But the databases are not comprehensive, and not all dismissals are accompanied by opinions. A 2011 study from the Federal Judicial Center that considered that larger universe, culled from electronic court files, found little change.

Professor Reinert’s study is even more detailed. It looked at more than 4,000 opinions and orders in 15 federal courts around the nation, and it considered more factors.

It may never be possible to untangle every confounding consideration. The financial crisis landed around the same time as Iqbal, and it had an influence on the mix of lawsuits filed in federal court. And it is impossible to count the suits never filed by lawyers who figured they could not win under the new legal standard.

But one trend seems clear. The cases that are dismissed early these days are often the ones brought by people rather than companies.

“Iqbal rewards lawyering, and it rewards access to information,” Professor Reinert said. “Both of those things come with access to resources.”