Over the past several years, a new wave of prosecutors have taken office in dozens of cities and towns across the country. Rejecting ineffective “tough on crime” policies that led to mass incarceration and unjust treatment of Black and brown Americans, these prosecutors have ushered in such promising reforms as smarter charging practices, reduction or elimination of cash bail, and new accountability and transparency measures for their operations. But bringing about change hasn’t been easy; local leaders have often faced pushback — indeed outright resistance — from entrenched interests. It is time for a national strategy.

More than 100 former and current prosecutors and law enforcement officials sent President Biden a letter urging him to establish a task force that would be charged with reimagining the work of local prosecutors to make the justice system less punishing and more equitable. The group recommended it be modeled after the task force on policing that President Barack Obama created in the wake of unrest over the police shooting of Michael Brown in Ferguson, Mo. During his election campaign, Mr. Biden advanced a criminal justice platform that included plans to create a task force to look at prosecutorial discretion and a White House spokesman, commenting on the letter, said the president remains committed to that proposal. But specifics about what the administration intends to do were not provided and that is disappointing.

Local prosecutors, as the group pointed out in their letter to the president, play critical and crucial roles in the judicial system but have been largely overlooked in the national debate about how to reform the system. Most of the emphasis in the reckoning that followed last year’s killing of George Floyd has been on police or the prison system.

The letter to the president was accompanied by a thoughtful research paper from Fair and Just Prosecution, an organization of newly elected prosecutors, including states attorneys and district attorneys, which outlined a proposal for organizing a task force and what it could achieve, as well as steps the federal government should take to ensure that any findings of the group don’t end up gathering dust on a shelf.

Putting a brighter spotlight on the role of local prosecutors would be an important first step. Miriam Krinsky, the executive director of Fair and Just Prosecution, called it a “black box” that needs to be opened. “If this administration wants to impact mass incarceration, address racial inequities and reset the criminal legal system, this is a key way to bring about meaningful and lasting reform,” said Ms. Krinsky, who is herself a former federal prosecutor.

Mr. Biden should make good on his campaign promise to examine how crimes are prosecuted and create this much needed task force.