Facing a lawsuit, the Education Department said this week it would no longer dismiss civil rights complaints simply because the filer had submitted other similar claims, reversing a policy that had led to the dismissal of hundreds of cases en masse.

In March, the department’s Office for Civil Rights updated its Case Processing Manual and said it would dismiss a complaint if it was part of a pattern of allegations, or if the complaint placed an “unreasonable burden” on the office.

That prompted a lawsuit from three civil rights groups alleging the policy had wrongfully cut off a critical avenue for students who believe their right to an education was being blocked. The suit is pending.

On Tuesday, the department’s assistant secretary for civil rights, Kenneth L. Marcus, released a revision to the Case Processing Manual, with that provision deleted. The new version also restores the right of appeal when the department finds insufficient evidence to substantiate a claim — another change.

Critics say the department was acting only because of the lawsuit.

“It is clear that this is a cover-your-rear litigation response,” said Catherine E. Lhamon, who led the Office for Civil Rights during the Obama administration and now chairs the U.S. Commission on Civil Rights.

The original provision appeared aimed at one activist, Marcie Lipsitt of Michigan. At the time it was put into place, she had 2,400 complaints pending regarding the accessibility of education websites for people who are blind or have other disabilities. Education Department officials referred to her and others as “frequent filers.”

Lipsitt said Tuesday that immediately after the March revision took effect, she had 671 complaints dismissed in large batches. She said that she tried to file new complaints by having her son submit the paperwork, but she said those were rejected, too.

“I am very cautiously hopeful,” she said Tuesday. “I have felt from the day those revisions were unleashed they were unlawful.”

The new manual retains another provision, also made in March, that limits investigations to individual allegations. It instructs staff to avoid systemic probes unless facts surface during an investigation that prompt a broader review.

The new manual encourages resolution of complaints through a facilitated conversation between the parties.

In another change, the update adds a provision stating the agency’s obligation to take actions consistent with principles enshrined in the First Amendment. It was unclear what purpose that provision is intended to serve, although a spokeswoman said that it related to “exercise of speech or expression.”

Some people who work in this field surmised that the provision relates to cases involving sexual harassment in which someone is accused of a civil rights violation based on something that was said. A department spokeswoman declined to offer further clarity.