Updated 2:01 p.m. |  U.S. Attorney for the District of Columbia Ronald C. Machen Jr. announced Monday that he will step down on April 1 and return to private practice. Machen’s investigation into a former D.C. mayor’s campaign will likely continue after his departure, though that probe drew some criticism from members of Congress.  

Machen will leave his post after more than five years, becoming the longest-serving U.S. attorney for D.C. in 35 years. After Machen leaves, Assistant U.S. Attorney Vincent H. Cohen Jr., a D.C. native, will become acting U.S. attorney. “I am proud of the work we have done together to achieve justice in the courthouse, and to build bonds of trust with the community that we serve,” Machen said in a statement.  

One of Machen’s high-profile cases involved former D.C. Mayor Vincent Gray’s 2010 mayoral campaign, in which prosecutors alleged that the former mayor personally solicited businessman Jeffrey E. Thompson to run a shadow campaign to help fund Gray’s campaign. In February 2014, Machen announced a plea deal with Thompson and warned his office would be unwavering in combating corruption in the District.

Rumors Gray could be indicted in office on corruption charges stemming from his 2010 campaign helped fuel current Mayor Muriel Bowser’s 2014 mayoral bid, when Gray lost in the primary. Some members of Congress have questioned the timing of the Justice Department’s plea deal, and how the February 2014 announcement might have unfairly influenced the city’s April 1 mayoral primary. Gray has yet to be charged in the case.

On Monday afternoon, Bowser’s office praised Machen for his service to D.C. “As one of the longest serving U.S. Attorneys in the District’s history, Ron Machen has worked hard day-in and day-out to do what’s in the best interest of the District’s residents and visitors,” Bowser’s spokesman Michael Czin wrote in an email to CQ Roll Call. “We thank him for his public service, wish him well on his future endeavors and look forward to working with Vincent Cohen as acting U.S. attorney.”

U.S. Attorney General Eric H. Holder Jr. cited Machen’s accomplishments while in office, noting that the prosecutor’s cases included protecting national security, investigating corruption of federal and local officials, combating violent crime and recovering financial assets.  

“As one of Ron’s predecessors as U.S. Attorney in Washington, I know firsthand the unique demands of leading the nation’s largest U.S. Attorney’s Office,” Holder said in a statement. “But Ron has never been deterred by a difficult challenge, nor slowed in his pursuit of a safer, stronger Washington.”  

Related:

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