The request comes during a federal criminal bribery case against Jefferson, with the Justice Department saying a parallel investigation could "complicate or impede the criminal prosecution," The (New Orleans) Times-Picayune reported Monday.

The committee will resume its probe into whether Jefferson violated House rules after his scheduled court date in January.

"While recognizing that the allegations involving Rep. Jefferson are of the most serious nature and must be addressed by the House, the investigative subcommittee concluded that it cannot move forward at this time without engaging in investigative activities that would risk interfering with the criminal prosecution and related ongoing investigation," read a statement posted on the House of Representatives' Committee on Standards of Official Conduct's Web site.