Mayor E. Muriel Bowser, right, her then-deputy mayor for education, Jennifer Niles, and then-Chancellor Antwan Wilson in November 2016. (Ricky Carioti/The Washington Post)

City investigators have concluded their examination into whether the former chancellor of D.C. Public Schools and the former deputy mayor for education — both of whom resigned this year amid controversy — violated the District’s code of conduct, an official said Thursday.

D.C. officials revealed in February that the District’s schools chancellor at the time, Antwan Wilson, bypassed the competitive lottery system so his daughter could secure a spot in a high school with a lengthy waiting list. The lottery system places students in schools outside their home zone. Jennifer Niles, deputy mayor for education at the time, resigned amid accusations she helped Wilson circumvent those rules.

Brent Wolfingbarger, director of government ethics at the D.C. Board of Ethics and Government Accountability, said Thursday at the panel’s monthly meeting that his staff had concluded the probe. But he said the office, which investigates D.C. government employees and officials accused of violating ethics laws, still needs to write a report on its findings.

The ethics board can levy fines and recommend the censure or firing of city officials. It is unclear when the report will be completed.

Mayor Muriel E. Bowser (D) said in February that Wilson months earlier had broken a policy banning preferential treatment of government officials’ children. Wilson wrote that policy months before, following an earlier scandal involving preferential treatment given to the children of prominent D.C. parents.

When Wilson’s family decided the school attended by his oldest child was not a good fit, Wilson approached the deputy mayor for education, and the teen was transferred to Woodrow Wilson High School in Northwest Washington without having to participate in the lottery.

Niles resigned immediately after the revelations, and Wilson followed days later after public pressure mounted for him to step down. Before he resigned, Wilson acknowledged his decision was “wrong” and apologized for skirting the lottery process.

After Wilson resigned in February, he told The Washington Post he informed Bowser months before the move became public that he was transferring his daughter to Wilson High midyear because she was unhappy at Duke Ellington School of the Arts. He said that the mayor never questioned him about his daughter’s move and that he believed at the time that the transfer was permitted.

Bowser has repeatedly denied she knew about the transfer.

Niles has not spoken publicly about the incident. Investigations by the ethics board typically include interviews with all parties involved.