The Justice Department’s pardon attorney is stepping down. (JIM LO SCALZO/EPA)

The Justice Department’s pardon attorney — charged with overseeing the review of clemency petitions from federal inmates — is stepping down at the end of January because she is frustrated by a lack of resources for one of the president’s centerpiece criminal-justice initiatives, according to people close to her.

The departure of Deborah Leff, who has been in her role since 2014, comes as the Obama administration struggles to process a backlog of more than 9,000 pending clemency petitions. As the president approaches the end of his second term, time is running out for his high-profile effort to offer clemency to certain nonviolent federal drug offenders harshly sentenced in the nation’s war on drugs.

The Justice Department said it is confident that Leff’s departure will not delay the administration’s clemency initiative, and it hopes to find a replacement quickly. Justice spokeswoman Emily Pierce also said the department is asking Congress to more than double the number of lawyers assigned to the pardon office, from 22 to 46.

Leff could not be reached for comment but released a statement saying that she has known President Obama for more than 20 years and that she thinks “his commitment to reinvigorating the clemency process — and the promise that holds for justice — can change the lives of a great many deserving people.”

But Leff added: “It is essential that this groundbreaking effort move ahead expeditiously and expand.”

A former trial lawyer, senior television producer and president of the Public Welfare Foundation, Leff was highly respected by sentencing reform advocates.

“She never got the staffing she needed,” said one friend. “She was very frustrated.” Other people close to Leff said that she was passionate about making the clemency initiative work but had been unhappy for quite some time about not having enough resources.

Obama has commuted the sentences of 184 federal inmates. White House Counsel Neil Eg­gleston said in December that Obama has commuted the sentences of more individuals than the past five presidents combined and that the president will grant more commutations and pardons this year.

But advocates of sentencing reform are disappointed that the clemency process has not moved more quickly and that more of the thousands who have submitted clemency petitions have not had their sentences commuted.

“I think it’s terrible timing in terms of the push to get more clemency grants before the president leaves office,” New York University law professor Rachel Barkow, a clemency advocate and co-founder of the Clemency Resource Center, said of Leff’s departure.

A senior Justice Department official said that the clemency initiative is of the highest priority for the department and that those involved have been working tirelessly to move petitions along as quickly as they can with a limited budget and legal restrictions.

The Office of the Pardon Attorney oversees all pardons and sentence commutations and makes recommendations for ultimate approval of the president. Leff’s recommendations first went to Deputy Attorney General Sally Quillian Yates, who then decided which petitions to recommend to Eggleston.

“To lose the head of the office that’s running the clemency initiative is concerning,” said Kevin Ring, vice president of Families Against Mandatory Minimums. “We hope she is replaced by someone who is as dedicated, smart, passionate and committed as she was to getting these petitions through.”

Pierce said the department has been constrained by law in terms of how many resources and how much of its budget it can devote to the clemency initiative. Pierce said the department has “provided additional funds to the pardon office within the confines of our budget and has detailed dozens of additional full- and part-time attorneys over the course of the clemency initiative.”

Despite the constraints, a Justice official said that lawyers are reading each of the thousands of clemency petitions that have been submitted and have prioritized the ones that best meet the new criteria set out by the administration.

On Monday, White House spokeswoman Brandi Hoffine said that Obama “thanks Ms. Leff for her years of service.”

“The president is deeply committed to the clemency initiative and continues to believe that clemency is an important way to spotlight, and remedy, some of the many injustices in our criminal justice system,” Hoffine said.

Justice officials said that they expect to name a replacement before Leff leaves Jan. 31.

“A new pardon attorney will be named in the near future and we expect the work of the pardon attorney’s office to continue apace as we identify and vet potential candidates for the president’s clemency priorities,” Pierce said. “The Justice Department is dedicated to the goals of the clemency initiative and is steadfastly committed to doing all it can to ensure fairness in the criminal-justice system.”