Faced with tough questions from state officials about pressure on educators to hand out diplomas, Prince George's County leaders continued to maintain Tuesday that the district's graduation-rate scandal resulted from failures in procedure and monitoring, not from any central-office orders.

Kevin Maxwell, chief executive in the state's second-largest school system, appeared with five other district officials before the Maryland State Board of Education, describing details of a plan to tighten controls on grading and graduation certification and responding to broader questions about what went wrong.

Board members asked about the school system's culture,attendance policies, late grading changes, the number of employees disciplined and regaining community trust. Their questions came as D.C. school officials have also been mired in a diploma controversy.

In Maryland, board President Andrew Smarick noted that while a state-ordered investigation had not found evidence that Maxwell urged improper conduct, it seemed that, given other findings, "something is going on here. I don't want to go too far, but it seems like some signal, something is happening to suggest to schools, to teachers, to someone, that you've got to graduate this student."

"There's too much smoke here . . . for us to say there's not something going on," he said.

Maxwell said that when he took over as the district's schools chief in 2013, some county schools used credit recovery programs that allow students to make up for work they have failed. He and others sought to more broadly open credit recovery to students.

"There was an inequity across the system," he said, calling it a fairness question and saying that helping kids be successful and meet standards is important work. "The question is, are people following — and it's clear they were not following — the procedures and policies that were in place around a number of these things," he said.

With the recent investigation showing where procedures need to be shored up, "we will do that," he said.

The exchange capped a meeting that produced some of the most pointed questions yet about the graduation-rates scandal, which came to wide attention last summer and led to the hiring of an outside firm that visited high schools, conducted employee interviews, examined student records and followed up on whistleblower complaints.

The investigation found that about 30 percent of a sample group of students with late grade changes lacked documentation that justified graduation or were clearly ineligible.

Tuesday's discussion came, coincidentally, as new data on graduation was released, showing another year of gains for Prince George's in 2017 with four-year graduation rates rising to 82.7 percent, up from 81.4 percent. Since 2013, the county rate has climbed by 8.6 points.

State board member Michael Phillips called the issue troubling and asked whether Prince George's leaders had discovered problems within the district's culture that spurred its missteps.

"We could be sitting here once again with the same issue if the culture does not change," he said.

Maxwell, who called the results of the investigation sobering, cited turnover in leadership and other staff positions that created confusion and accountability gaps. He also noted that many procedures at issue were not automated. That will change under the district plan.

"What we've been trying to do is come in in a lot of different areas and improve the systemic policies and procedures and structures and systems that we have and make sure we are focused on accountability, that we're focused on acting with integrity, that we're focused on the things that our system needs to do," he said.

State board members asked about the number of employees who had been disciplined in the wake of the scandal. Last week, five DuVal High School employees were removed following findings that grading and graduation certification procedures were violated.

At the Tuesday meeting, Maxwell described the number as "about five or six."

State Board of Education Member David Steiner called for answers to several basic questions. His first: "So we will never see again students with 50 days of absences graduating from your system?"

In 2017, 159 students graduated despite more than 50 days of unexcused absences.

"Not unexcused," one of Maxwell's top administrators told him.