A federal prosecutor who helped convict former Prince George’s County Executive Jack B. Johnson (D) in a far-reaching corruption case is among three lawyers in the Maryland U.S. Attorney’s office who have won promotions.

Sujit Raman, who assisted in the Johnson case and worked on 14 other related corruption cases is the new head of the appellate section, U.S. Attorney Rod J. Rosenstein announced Wednesday.

Also promoted were Kathleen O. Gavin to chief of the corruption section, and Thomas F. Corcoran to deputy chief of the civil division.

“Maryland is fortunate to have a deep bench of talented Assistant U.S. Attorneys whose work is worthy of public confidence,” said Rosenstein in a written statement.

“These new supervisors will help us maintain the office’s reputation for excellence and integrity while we seek to promote the rule of law, deter crime and protect government property.”

Raman, a graduate of Harvard and Harvard Law School, worked in private practice for three years before joining the U.S. Attorney’s Office in 2008. In addition to his work on the Prince George’s cases, he has argued several cases in the U.S. Court of Appeals.

Gavin spent five years as a private law firm associate before joining the U.S. Attorney’s Office in 1991. She handled the prosecution of Prince George’s State Sen. Ulysses Currie (D), which resulted in Currie’s acquittal on corruption charges.

She recently prosecuted the Operation Towhook wiretap case that resulted in federal extortion convictions of 17 defendants, including 15 Baltimore City police officers.

Among other significant cases Gavin handled was the successful prosecution of Maryland State. Sen. Thomas Bromwell (D-Baltimore) on corruption charges. He was accused of using his official position and influence in exchange for payments and other benefits.

She is a graduate of the University of Virginia and the University of Maryland law school.

Corcoran, a graduate of Cornell and Tulane law school, spent eight years in private practice litigating commercial cases before he joined the U.S. Attorney’s Office in 2002. Corcoran’s recent cases include settlements with Boehringer Ingelheim Pharmaceuticals ($95 million); Novo Nordisk ($25 million) ; Dava Pharmaceuticals ($11 million); St. Joseph’s Medical Center ($4.9 million); and Advanced Bionutrition ($1 million), Rosenstein’s statement said.

Corcoran also resolved cases with Chesapeake Youth Center; Advanced Centers for Orthopaedic Surgery; Sleep Solutions; and Woodhaven Pharmacy. In 2011, he assisted in the criminal prosecution of Dr. John McLean, who was sentenced to eight years in prison for implanting unneeded cardiac stents.