Sofia Uriagereka-Herburger, a 10th grader, speaks into the megaphone. Students from Duke Ellington School of the Arts protest concerning the investigation into residency violations in front of the Office of the State Superintendent of Education headquarters in Washington. (Sarah L. Voisin/The Washington Post)

The city agency presiding over an investigation at Duke Ellington School of the Arts conceded Wednesday it had mishandled for a second time the process of notifying 164 families that they are accused of fraudulently enrolling in the public arts school.

A D.C. Superior Court judge dismissed a case Wednesday against the Office of the State Superintendent of Education after the agency agreed to resend notices to families explaining why they are accused of fraud. The families are accused of living outside the city and fraudulently enrolling their children in the school without paying the tuition required of suburbanites who attend D.C. schools.

This is the second time in two weeks the agency acknowledged in court that it made missteps in an investigation that rocked the celebrated institution. These will be the third notices that families have received.

The superintendent’s office did not respond to a request for comment.

The cases of the 164 families — nearly one-third of the school’s student body — have been forwarded to the Office of the Attorney General.

“Our responsibility is to defend D.C. agencies in court,” Attorney General Karl A. Racine (D) said. “We look forward to working with the agency to draft notices that will be compliant under city law.”

The withdrawal of the current notices does not change the accusations.

When the superintendent’s office sent the initial notices to families last month, it did not explain the allegations or inform parents how they could appeal their cases. The second notices laid out the appeals process but did not explain the basis for the allegations.

The new notices will restart the clock for appealing the cases, giving families 10 business days to appeal.

Greg Smith, a lawyer and Ellington parent who drafted the legal complaint on behalf of the families, said that many families accused of residency fraud live in the city and do not understand why they are tangled in this investigation.

“When Ellington families tried to find out why, [the superintendent’s office] gave no clue why its Notice letters (often sent to the Ellington families’ DC addresses) declared them nonresidents,” Smith, who is not accused of fraud, wrote in an email.