The Manhattan district attorney's (DA) office has agreed to drop fraud-related charges against former Dewey & LeBoeuf junior manager Zachary Warren under a one-year deferred prosecution agreement.

Warren's agreement includes a commitment to complete 350 hours of community service. If he complies, prosecutors will move to dismiss charges of scheme to defraud and conspiracy in a year.

This is a second deal the district attorney's office has made with a former Dewey defendant. Warren's agreement has no restrictions on practising law. His lawyers announced that he will start as an associate this autumn at Williams & Connolly.

In March 2014, prosecutors announced an indictment with more than 100 counts against Warren and three ex-Dewey executives, Steven Davis, Stephen DiCarmine and Joel Sanders, alleging that the four took part in a scheme to defraud the firm's lenders and creditors. Warren's trial was separate from the three executives.

After a five-month trial, a jury declared a mistrial against the three executives, and the DA's office subsequently dropped multiple lower level charges against all four defendants.

Last month, Davis, the firm's ex-chairman, signed a non-prosecution agreement, under which he will avoid a retrial. He cannot practise law for five years in New York, and he may never appear before the US Securities and Exchange Commission.

The retrial of the two remaining Dewey defendants has been set for September before Acting Supreme Court Justice Robert Stolz.

The DA's office had claimed that Warren helped plan fraudulent accounting entries and took part in covering them up. He was scheduled to go to trial next month.

Warren left Dewey in mid-2009 to attend Georgetown University Law Centre, before the firm's private bond offering and its 2012 collapse. Many legal observers questioned the charges against the junior manager, who was 29 when he was indicted.

In the deferred prosecution agreement, Warren maintains his innocence of any crime, while the DA's office maintains that "[Warren's] guilt would be proven by evidence that he knew about Dewey's covenants, how Dewey accounted for fees and disbursements, and about the accounting scheme at Dewey," as well as that he took part in aspects of the scheme.

Joan Vollero, a spokeswoman for the Manhattan district attorney's office, said in a statement that Warren's agreement is "unrelated to the strength of the case".

"We are confident that, had this case proceeded to trial, we would have met our burden of proof," she said. "While the crimes with which Mr Warren are charged are serious, his overall culpability is different from that of the remaining defendants, and we believe he engaged in that conduct at the direction of his supervisor, former chief financial officer Joel Sanders."