D.C. Fire and EMS Chief Kenneth B. Ellerbe poses for a picture after an interview with The Washington Post at the John A. Wilson Building on June 4, 2014, in Washington, D.C. (Ricky Carioti/The Washington Post)

Early in 2011, a few weeks after he was named chief of D.C. Fire and Emergency Medical Services, Kenneth B. Ellerbe was asked about his plans for the department where he had spent nearly his entire adult life.

“We’re going to make it fair,” Ellerbe said in remarks later posted online. “We’re going to give everybody a level playing field.”

His stormy 31 / 2-year tenure became better known for the department’s numerous well-publicized missteps — among them, incidents in which a badly injured police officer was forced to wait at least 15 minutes for an ambulance and firefighters failed to respond after a man collapsed after a heart attack across from their station house and later died.

Ellerbe’s leadership, for better or worse, also brought long-simmering tensions within the department to a full boil. Those tensions are rooted in a debate over the size, shape and mission of a department charged with protecting a changing city, but they have also grown out of generations of differences concerning culture, geography and tradition.

With Ellerbe now departing, the District’s next mayor will be faced with a task much more complicated than simply choosing a new manager for the 2,000-member department.

Debates over the shifts firefighters work, how they are recruited and trained, the jobs they are expected to do and how they are deployed to do them remain highly antagonistic, contributing to a fractious — if not openly hostile — relationship between department’s leadership and the rank-and-file.

Both leading mayoral candidates — Democratic nominee Muriel Bowser and independent David A. Catania, also both D.C. Council members — have said they would dismiss Ellerbe if elected, making his planned July 2 departure unsurprising.

But in interviews Thursday, the candidates staked out different positions on some of the key questions about the future of the fire department, including how to handle Ellerbe’s controversial proposal to change firefighter shifts and how the new chief should be recruited.

Bowser (D-Ward 4), who says she has engaged in “stakeholder conversations” in recent weeks about the department, said she would embark on a nationwide search for Ellerbe’s replacement. “I think that the current leaders in the fire department should be given every chance to show their vision, but I do think a widespread search would be appropriate,” she said.

She declined to take a hard position on the shift proposal: replacing the schedule of 24 hours on, 72 hours off with shorter shifts, which has generated vehement objections from firefighters, some of whom live far from the city.

“My current thinking is that we focus on how we work with our employees and make sure that we have a schedule and shifts that are responsive to the needs of their residents,” Bowser said. “I would want to look at that proposal with a fresh set of eyes.”

Catania (I-At Large), however, said he would place the shift-change proposal on the back burner in an attempt to restore the relationship between the department brass and front-line personnel.

“I would rather us focus on those issues where we can find common ground first,” he said. “If, as mayor, I were to begin with the singularly most controversial issue facing the department, that hardly strikes me as setting the right tone for the department.”

Catania also said that because he wants to foster the “organizational development” of the department, he would be reluctant to recruit an outsider to lead the force. “It sends a very bad message to the rank-and-file employees if they never believe they’ll have a chance to lead the department,” he said. “We need to create a trajectory that people who are risking their lives for us have the possibility to rise to the top.”

Ellerbe’s departure holds the promise of at least a temporary labor-management détente. Edward C. Smith, who leads the 1,800-member International Association of Firefighters Local 36, said he looks forward to working with a new chief to “restore the department to where it should be.”

“It is a chapter in this department that I’m glad is over,” Smith said.

Eugene Jones, an Ellerbe deputy who was a former chief of the Prince George’s County Fire/EMS department, will be acting chief. Mayor Vincent C. Gray, who lost his bid for a second term in the Democratic primary this spring, said Thursday that he does not intend to engage in a broader search before he leaves office in January.

Dave Statter, a fire department communications consultant and former radio and TV reporter who covered the D.C. department over three decades, said it could be difficult for the next mayor to recruit a top-notch outsider.

“The politics that surround this department will have a lot of candidates being very cautious about taking this job,” Statter said. “There’s no doubt there’s still talent in the department. . . . The new mayor will have to look carefully at what is reality about those people versus what they may have been led to believe by the previous administration.”

Outsiders will be watching the search closely. Among them: the families of those whom the department has failed.

In January, firefighters inside a station in Northeast Washington ignored cries for help after 77-year-old Medric “Cecil” Mills Jr. collapsed across the street. He later died.

The Mills family, through their attorney Karen Evans, said that Ellerbe should have resigned immediately after their relative’s death. “We hope this departure ushers in a new, safer, and more responsible era for the delivery of emergency services in our nation’s capital,” the family said in a statement.

But Marcus Rosenbaum was more complimentary of Ellerbe. His brother David died in 2006 after emergency personnel mistook injuries suffered during a mugging for signs of drunkenness and labeled the incident a low-priority call. Rosenbaum said that Ellerbe is the first chief since then to treat medical calls as a priority.

After Rosenbaum’s death, the D.C. inspector general noted a “culture of indifference” among some firefighters who felt disdain about helping out on ambulance runs.

More than 80 percent of emergency calls are for medical issues, not fires, and a commission that studied the Rosenbaum case concluded that cross-training paramedics and firefighters was essential to ensuring that the department keep pace with the new reality.

“What happened to Mr. Mills was just horrible,” Marcus Rosenbaum said. “But when my brother died, the immediate response from the fire department and from everybody was that, ‘We didn’t do anything wrong. We were following procedure.’ This time, thank God, they didn’t do that. The chief said this is horrible. The deputy mayor said this is horrible. Even the union said this is horrible. And they were all right. Nobody tried to give any excuses.”