This was originally posted on The Huffington Post .

Should the government be allowed to lie to the courts in the name of national security? This is the question that judges on the Ninth Circuit Court of Appeals will have to consider in the next few weeks.

On Monday, the American Civil Liberties Union of Southern California (ACLU SoCal) asked the full Ninth Circuit to rehear a case in which the government repeatedly lied to a federal district judge about the existence of FBI surveillance documents.

If the judges of the Ninth Circuit fail to act, there will be grave repercussions for government transparency. Federal courts provide a check on the government's abuse of power -- a check that is more critical now than ever before, as individual judges decide so many fundamental questions about our rights in private, with nothing but the government's assurances to guide them. Allowing the government to lie to these very same courts -- knowing that there will be no punishment if they are caught -- puts the integrity of our judicial system at risk.

ACLU SoCal filed the Freedom of Information Act (FOIA) case Islamic Shura Council v. FBI on behalf of several prominent, law-abiding Muslim community leaders and organizations who wanted to uncover information about the FBI's surveillance of them. The FOIA is a law Congress passed that gives courts the authority to order the government to turn over information to the public.

While the government disclosed some documents -- which revealed, among other things, that the FBI has spied extensively on the peaceful activities of Muslim community organizations, including their participation in immigration reform rallies -- it also lied to the court about the number and content of the documents it had kept secret. Only when U.S. District Judge Cormac Carney discovered the lies did the government reveal the whole truth and defend its actions, claiming that it had to mislead the court because even acknowledging the existence of the documents would have posed a threat to national security.

Courts have the power to impose sanctions for lies, and Judge Carney did so, fining the government for deceiving him. But the government appealed to the Ninth Circuit, and in July a three-judge panel ruled that the government could not be sanctioned. Why? The panel found that the government eventually "corrected" its lies -- even though it did so only after the judge uncovered the lies and ordered a full explanation.

The full court could -- and should -- rehear this case. The power of federal judges to review the conduct of the executive branch, both in FOIA cases and in others, hangs in the balance.