NEW ORLEANS (AP) — A federal appeals court in New Orleans on Monday became the latest to hear arguments on whether President Joe Biden overstepped his authority with an order that federal contractors require that their employees be vaccinated against COVID-19.

The contractor mandate has a complicated legal history. It is being challenged in more than a dozen federal court districts, and the mandate has been blocked or partially blocked in 25 states. At one time, enforcement was blocked nationwide under a ruling by a Georgia-based federal judge. But an appeals court in Atlanta narrowed the scope of that ruling to the seven states that had sued in that case.

government website says the mandate isn’t being enforced while legal challenges play out in various jurisdictions around the country.

Biden administration lawyers defended the mandate Monday at the 5th U.S. Circuit Court of Appeals. They hope to vacate a ruling by a federal judge in western Louisiana who said the mandate couldn’t be enforced in contracts between Indiana, Louisiana or Mississippi and the federal government.

Judges repeatedly asked Justice Department attorney David Peters about limitations on presidential power under federal law. They asked whether a president could go so far as to require that contractors only hire people from homes where there are no smokers, or where birth control is used.

A rule aimed at contractors’ family members would be out of bounds, Peters said. But the vaccine requirement for contractors’ employees was legal under federal law that gives the president the authority to manage contracts economically and efficiently, he said.

“Presidents have consistently used this authority in a way that addresses meaningful limitations and threats,” Peters said.

Elizabeth Murrill of the Louisiana Attorney General’s Office argued that the administration went too far in a matter that affects contracts in three states involving more than $100 billion in spending.

“They have not produced any limiting principle on their theory,” she told the panel.

Murrill also made much of a Biden interview that aired in mid-September in which he said the pandemic was over, a remark he later clarified after facing heat from health experts, who worry the message might slow prevention efforts.

The panel at Monday’s hearing consisted of Judge James Graves, a nominee of President Barack Obama, and judges Don Willett and Kurt Engelhardt, both nominated to the court by President Donald Trump. The judges did not indicate when they will rule.