As the District’s mayor embarks on the politically fraught process of choosing a new police chief, pressure is building for a leader who embraces a public health approach to fighting crime and will find alternatives to relying on law enforcement.

Lawmakers and other groups are calling Chief Peter Newsham’s departure next month to lead police in Prince William County, Va., an opportunity for a vast reimagining of policing in the nation’s capital that de-emphasizes arrests and redirects resources into programs that address the root causes of crime.

On Thursday, the council’s Committee on the Judiciary and Public Safety heard from more than 40 witnesses exploring alternatives to traditional policing, such as sending counselors on calls to people suffering from mental health crises or drug addiction.

“Policing has long been seen as the default or, in some cases, the only response to behavior society doesn’t like or doesn’t know how to solve,” said Council Member Charles Allen (D-Ward 6), the committee chairman. “We have created a culture where an officer with a badge and a gun is expected to save the day,” even when other agencies might be better suited.

Allen said the District has failed to integrate police and social services, “and other jurisdictions are frankly lapping us.” And, he said, “We don’t have a continuum of emergency response that includes the many programs we do run.”

Mayor Muriel E. Bowser (D) has largely been silent on how she plans to replace Newsham and what direction she wants her new police leader to take. She has objected to several council initiatives, including cutting the police budget and a bill that would allow offenders who committed crimes before the age of 25 to seek release after 15 years in prison, saying it does not take victims into account.

Bowser said she plans to select an interim chief soon and has not indicated whether Newsham will remain through the Jan. 20 presidential inauguration, as he has said he intended.

At a news conference Monday, Bowser said choosing a new police chief “is an awesome responsibility, and it is one of the most important personnel selections that a mayor or a chief executive will make.” She gave a brief nod to people calling for change, saying, “Now, especially with the climate we are in, public officials are under a lot of pressure to make the right choice.”

A Police Reform Commission developing a plan to rethink policing in the District is pushing the mayor to include the public in her selection process, calling it a moment “to build trust and strengthen the legitimacy” of the new chief.

The chairman of the D.C. Council has said the mayor should promote from within the force, while Monica Hopkins, executive director of the ACLU of the District of Columbia, is urging a nationwide search, saying in a statement a “toxic culture infects all levels within the department.”

Hopkins, testifying at Thursday’s council hearing, challenged lawmakers to not prioritize police and instead “reinvest in the community.” She urged the council to “hold the mayor accountable to appointing a chief of police that shares this vision.”

No one from the Bowser administration testified at the hearing. Allen said he contacted D.C. police, the Department of Behavioral Health, the Fire and Emergency Services department and the deputy mayor for public safety, and “they all declined.”

Instead, the mayor’s office submitted written testimony after the hearing ended from the director of the Lab @ DC, which crunches data to help the city make policy decisions, emphasizing an effort earlier this year on understanding and reducing racial bias in police stops in the District.

Data and studies, the statement says, are a way to explore alternatives to police stops and “an example of how we might effectively approach the broader conversation in a collaborative manner.”

Nearly all the people who testified supported changing the way police work, some by cutting funds, others by removing officers from schools, most by shifting responsibilities away from law enforcement. Some cited efforts in other cities.

In Denver, dispatchers can route emergency calls to clinicians and paramedics.

Vinnie Cervantes, director of the Denver Alliance for Street Health Response, said a single van has responded to 800 calls since a pilot program started in June, most related to complaints of trespassing and wellness checks, which often involve people experiencing homelessness and drug addiction.

For now, the program is limited in hours and geography, and plans to expand are at least a year away. But Cervantes said many people have already been “spared from being arrested and jailed.”

Some of the most vexing testimony came from people harmed by violence in the District, yet even they said police are just one part of a vast structure of city services and agencies that needs to be revamped.

“Reform is not enough,” said Ra’Mya Davis, a junior at Thurgood Marshall Academy Public Charter High School and a member of a program addressing youth violence. “We have to reimagine what our community looks like.”

Davis noted two students from Thurgood Marshall killed during the 2017-18 academic year and said, “Sadly, the loss of friends to gun violence is not unique to our school or to my friends.” But, she said, “police aren’t the answer to solving these problems,” and she described a program in her school to mediate disputes and fights without involving law enforcement.

Roger Marmet, whose 22-year-old son, Roger “Tom” Marmet, was fatally shot in the District in 2018 when police said he was struck by a stray bullet while stopped in his vehicle at a traffic light, called for a comprehensive program to address violence at every level of government and society.

Marmet said many underlying causes of crime are best handled outside the scope of law enforcement, and he called the council’s actions so far inadequate. He said other cities have successfully embarked on paths to reduce both violence and policing, but he told lawmakers it won’t come “piecemeal, with one-off legislation” that isn’t “laser-focused on the small number of individuals who largely drive the gun violence.”

Marmet, whose son was killed while driving home from volunteering to help recovering drug addicts, said intervention programs need to start early and target hardcore offenders and involve the entire array of government services. He mentioned changes in Oakland, Calif., where he said “arrests are no longer the measure of success. An arrest for a homicide is seen as a failure to stop violence before it happens. In D.C., every homicide is a failure of this council and of my own advocacy efforts.”

Michael Brice-Saddler contributed to this report.