Q: A friend and I have been following former Rep. William Jefferson’s (D-La.) appeal of his conviction for bribery. Over the holidays, I read that the appeal could significantly impact federal law regarding bribery. Can you help me understand what is at stake in Jefferson’s appeal?

A: Say you are a toothbrush manufacturer and you go to your local Congressman and offer him $10,000 to vote for legislation promoting the use of toothbrushes. You would be guilty of bribery under federal law.

Say, instead, that you go to your local Congressman and offer him $10,000 to brush his own teeth. You would not be guilty of bribery.

What’s the difference? The answer lies in the definition of bribery, which is at the heart of one of Jefferson’s main challenges to his conviction. But first, some context.

In November 2009, Jefferson was convicted of multiple felonies resulting from allegedly accepting bribes while a Member of Congress for performing constituent services, including helping several companies do business in the United States and West Africa. The charges are primarily based on violations of the federal bribery statute and a law prohibiting what is known as “honest-services wire fraud.” Jefferson’s challenges to his honest-service wire fraud alone are enough fodder for a column. Your question concerns bribery, so let’s focus on that.

To convict a public official under the federal bribery statute, the government must prove that the official solicited or accepted something of value in return for “being influenced in the performance of any official act.” At issue in Jefferson’s appeal is what counts as an official act. Voting on toothbrush legislation is an official act. Brushing one’s teeth is not.

Jefferson contends that his trial judge improperly instructed the jury regarding the definition of an official act and that resulted in his conviction. The judge first told the jury the statutory definition of an official act — any decision or action on any matter that may be pending or brought before a public official in his official capacity. Then, at the government’s urging and over Jefferson’s objection, the judge told the jury that official acts include activities  “clearly established by settled practice as part of a public official’s position.”

Jefferson argues that this instruction was erroneous because it would make the bribery statute unconstitutionally vague. Jefferson particularly focuses on the phrase “settled practice.” What does it mean for a practice to be settled for a Member of Congress, he asks? That a majority of Members do it? That one or two Members do? How often? And can a practice that was once settled become unsettled? Jefferson argues that if an “official act” were to include anything that could be construed as a “settled practice,” officials would not have sufficient notice of conduct prohibited by the bribery statute.

The government makes several points in response. First, the government says, the judge did not use the term “settled practice” as a substitute for the statutory definition of “official act.” Rather, after reciting that definition twice to the jury, the judge merely went on to clarify that an act may be official even if it is not part of a responsibility explicitly assigned by law but instead clearly established as part of an official’s position by settled practice.

Second, the government says, the term “settled practice” is everyday speech, and an official could therefore easily understand what actions could be “clearly established.” Indeed, the term appears in many U.S. Supreme Court decisions.

Third, the government argues, Jefferson himself is in no position to challenge the clarity of the “settled practice” instruction because Jefferson himself clearly knew that he was illegally performing official acts in exchange for bribes. In other words, even if the term “settled practice” creates vague borders, Jefferson’s actions were nowhere near those borders.

For example, the government says, Jefferson issued a Congressional inquiry to the Army for the benefit of a company that was bribing him; promoted the company’s product to a committee chairman, who wrote on Congressional letterhead endorsing the product; and led an official delegation to Nigeria, where he lobbied officials for the benefit of the company.

These acts, the government says, are all indisputably official acts. For the travel to Nigeria, the government notes, Jefferson filed forms with the House certifying that his travel was in connection with his official duties. In sum, the government says, Jefferson “consistently deployed all the trappings of his Congressional office,” including access to staff members, embassy limos and House stationery, to ensure that the constituents who bribed him received the influence they were purchasing.

So, what to make of this? Jefferson’s appeal is now in the hands of the Fourth Circuit Court of Appeals, which heard oral arguments in December. Unfortunately for Jefferson, even if the Fourth Circuit were to find compelling Jefferson’s argument about the vagueness of “settled practice,” this would not necessarily make Jefferson a free man or even get him a new trial. Jefferson was convicted on 11 counts, each with slightly different factual or legal bases. If the court upholds convictions on just one of the counts, Jefferson would remain imprisoned for many years. Only a home run — a complete reversal of all convictions — would set Jefferson free.

Nonetheless, you are right that the court’s decision could be significant to federal bribery law. Political law attorneys will certainly be watching closely. And perhaps some public officials will be, too.

C. Simon Davidson is a partner with the law firm McGuireWoods. Click here to submit questions. Readers should not treat his column as legal advice. Questions do not create an attorney-client relationship.