A federal prosecutor warned Friday that if the conviction of former Rep. William Jefferson (D-La.) is reversed on appeal, it would place many fraudulent acts committed by lawmakers outside the scope of current bribery law.

Jefferson was convicted of 11 corruption charges in 2009, but his legal team is arguing that since the former Congressman’s scheme to connect businesses in which he had a financial stake with foreign governments was not related to his formal legislative duties, his activities are not covered by the bribery statute under which he was prosecuted.

Government prosecutors say agreeing with Jefferson’s argument would require a narrow interpretation of the law that is unprecedented.

“Congressman Jefferson asks this court to do something that no other court has done before. He asks this Court to find that a significant part of the job of a Member of Congress should be excluded from the reach of the federal bribery statute,” Assistant U.S. Attorney Mark Lytle told a three-judge panel of the 4th U.S. Circuit Court of Appeals during his closing arguments.

“Neither the text of the statute, its legislative history, the cases analyzing it, nor Congressman Jefferson’s own words and actions support such a proposition,” Lytle added.

Jefferson, 64, represented the district that includes most of New Orleans from 1991 to 2008.

Federal prosecutors alleged — and a jury agreed — that Jefferson committed multiple felonies during a years-long scheme to line his pockets that included demanding retainer payments and stock shares from businesses he agreed to promote during trips to Africa.

During visits to countries that included Cameroon and Nigeria, Jefferson would represent these businesses by using his position as a Congressman and government resources to gain access, including embassy-paid motorcades and letters sent on official stationary, court records show.

Executives of those firms would then send payments of cash and stock to companies that were owned by Jefferson’s family members but controlled by the Congressman, according to court filings.

Jefferson’s appeal hinges not on whether he committed the offenses for which he was convicted but what legal experts call a “novel” theory that the trial court judge erroneously defined key legal terms in the federal bribery statute for the jury.

Jefferson’s legal team argues that U.S. District Court Judge T.S. Ellis incorrectly told jurors that an “official act” for the purposes of a bribery conviction is “activities that have been clearly established by settled practice as part [of] a public official’s position.”

His attorneys also take issue with the fact that jurors were told a quid pro quo scheme could be established even if Jefferson only performed those acts on an “as-needed basis.”

Because Jefferson arranged meetings between private companies with foreign governments on his own time and they did not relate to the Congressman’s formal legislative duties, he was not engaged in an official act that falls under the bribery statute prosecutors used to secure his conviction, Jefferson’s lead appellate counsel, Lawrence S. Robbins, argued Friday.

“Whether or not this court reverses the conviction … turns on whether the instructions given to the jury … were manifestly incorrect,” Robbins said during his argument.

The judges seemed largely skeptical of the former Congressman’s legal argument that his actions were not related to his official duties. They took turns posing hypothetical situations about actions that are widely thought to be the duties of a lawmaker but are not explicitly defined by rule or law.

“Does a Congressman have a binding duty to vote … where is that [written]?” Judge Allyson Duncan asked.

“You’d say that once they leave the Capitol building nothing falls under this statute, is this true?” Judge Robert King asked.

Robbins said yes.

Government prosecutors argued that Congress wrote the bribery statute to be intentionally broad lest too many misdeeds fall outside its scope.

“The argument that I think the U.S. attorney is making is that this would open us up to the possibilities of public corruption or insulate against that behavior,” said Carl Tobias, a professor at the University of Richmond School of Law. “And that’s a strong argument to make — there’s a sensitivity to public corruption cases.”

The 4th Circuit typically takes about two months to release its written opinion, attorneys say. At that point, Jefferson could ask for a re-hearing before the full court if he is unsatisfied with the outcome. If that request is denied, he could ask the Supreme Court to hear his appeal, though it would be statistically unlikely that the high court would take the case.

Decisions of the 4th Circuit set a precedent for federal courts in Maryland, North Carolina, South Carolina, Virginia and West Virginia.