Federal prosecutors in the District said Thursday that they will launch the first conviction integrity unit within a U.S. attorney’s office to identify potential wrongful convictions, responding to a series of exonerations in the past five years stemming from flawed FBI forensic evidence and testimony.

In an interview, U.S. Attorney Ronald C. Machen Jr., the District’s top prosecutor, said he will add resources to his office’s 13-attorney Special Proceedings Division, led by Chief Leslie Ann Gerardo, and assign at least two attorneys to investigate questioned convictions. They also will be tasked with recommending practices for investigators and prosecutors to help avoid future errors.

The division now is responsible for opposing defendants’ post-conviction appeals before the D.C. Superior Court and the U.S. District Court for the District.

“As prosecutors, our goal is not to win convictions, but to do justice,” Machen said in an interview before the formal announcement Friday. “This new unit will work to uncover historical injustices and to make sure that we are doing everything in our power to prevent such tragedies in the future.”

Prosecutors in several large U.S. cities — including Dallas, New York, Chicago, Philadelphia, San Jose, Cleveland and Detroit — have set up such units in recent years, sometimes inviting external reviewers to root out erroneous convictions.

The move reflects the District office’s unusual role in prosecuting crimes handled elsewhere by state and local prosecutors.

Since 2009, Machen’s office has acknowledged that errors by an elite FBI forensic unit dating to the 1980s led to five convictions that have been overturned through DNA testing, beginning with Donald E. Gates and including most recently, in a case identified by prosecutors, Kevin Martin.

Machen said the unit will look into convictions that come into question and refer findings to a new Conviction Integrity Committee that Machen said he will name. That committee will be comprised mostly of senior prosecutors from his office but include at least two defense attorneys.

Shawn Armbrust, executive director of the Mid-Atlantic Innocence Project, which has worked with Machen’s office, called the unit an important practical step that could help defendants seeking exoneration avert years-long litigation through cooperation, and she said she hoped that it would allow for some transparency so that the unit was not just “prosecutors reviewing prosecutors.”

She added: “It is an important cultural step for the office to officially recognize that there are wrongful convictions in the District of Columbia, and there may be enough of them to necessitate the formation of this unit.”

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