Gov. Christie has named John J. Hoffman of Marlton to serve as acting attorney general of New Jersey during former Attorney General Jeffrey S. Chiesa's service in the U.S. Senate.

Hoffman, 47, was executive assistant attorney general for under Chiesa prior to his appointment, announced Monday.

For reasons he did not explain, Christie passed over Chiesa's deputy, Thomas R. Calcagni, who remains the department's first assistant attorney general.

Earlier in the day, Vice President Biden swore Chiesa in to fill the seat left vacant by the death June 3 of Sen. Frank Lautenberg. The first Republican to represent New Jersey in the Senate since 1982, Chiesa will serve until voters elect a new senator in a special October election.

Christie has not said if he will return Chiesa to the attorney general's post when he leaves the Senate.

Under Chiesa, Hoffman served as acting attorney general for civil cases during the attorney general's absences or recusements, and on a regular basis oversaw the Division of Law and Public Safety and departments regulating civil insurance fraud and gaming.

Hoffman was not available for comment Monday. In a prepared statement he said he would continue to work from Chiesa's agenda.

Between 2006 and 2012 Hoffman served as an assistant attorney in the U.S. Attorney's Office for the District of New Jersey, where he specialized in white-collar and economic prosecutions. For two of those years he served under Christie, who was U.S. Attorney from 2002 to 2008.

Chiesa and also worked in the U.S. Attorney's office with Christie.

Hoffman previously worked in Washington as a trial attorney for the civil division of the U.S. Department of Justice, and in private practice for the law firm of Akin, Gump, Strauss, Hauer and Feld.

In 2004 he and his wife bought a home on a golf course in the Marlton section of Evesham for $790,000.

He graduated in 1987 from Colgate University, and in 1992 from the Duke University School of Law, and later clerked for Judge Al Engel on the Sixth Circuit United States Court of Appeals.

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