New York(CNN) Lawyers for Deutsche Bank and Capital One repeatedly refused Friday to tell an appellate court in New York whether the banks are in possession of President Donald Trump's tax returns, citing "contractual obligations" not to disclose the information and drawing the ire of a panel of judges.
The three-judge panel was so frustrated by the lawyers' refusal to answer that one of the judges suggested the appellate court might seek an order for the information.
"Should we go to court and seek an order? I'm serious. We need to know," US Circuit Judge Peter W. Hall told a lawyer for Deutsche Bank, Raphael Prober.
After several minutes of argument on the subject, the panel directed the lawyers to file letters under seal within 48 hours saying whether the banks have Trump's tax returns. But while the banks' lawyers indicated they would respond in writing, it wasn't clear that they agreed to provide that information.
The dispute came during oral arguments before the 2nd US Circuit Court of Appeals in Trump's appeal of a lower court ruling that rejected his attempt to block Democratic lawmakers from accessing his financial records through subpoenas of those banks.
The heart of the dispute is whether the subpoenas were issued pursuant to a legislative matter, which lawyers for the US House of Representatives have argued, or whether their true purpose is an attempt by Congress to improperly aid law enforcement, which Trump's lawyers contend.
In May, US District Judge Edgardo Ramos refused to block the subpoenas from the House Intelligence and Financial Services committees, ruling that the panels seeking Trump's financial information have legitimate legislative purposes.
The subpoenas are broad, Ramos said, but they are "clearly pertinent" to Congress' work and "do not constitute impermissible law enforcement activities."
A lawyer for the House reiterated Friday that the subpoenas are at least in part intended to aid an inquiry into possible money-laundering activities that could result in banking policy revisions and to investigate the President's financial dealings with foreign powers, such as Russia.
"Why is it that Deutsche Bank would lend him money when no other bank would touch him?" Douglas Letter, general counsel for the House, said Friday.
"Then what is the legislative purpose?" said a member of the panel, Judge Debra Ann Livingston. "It's law enforcement."
Letter disputed that, saying the committee intends to use the subpoenaed material to determine whether there should be additional banking regulation that might curb the type of loans Trump received.
"Russian oligarchs and others, their money is pouring into the United States and being used in real estate transactions and others," he said.
An attorney for Trump, Patrick Strawbridge, countered that the subpoenas, which seek records from Trump's family members, including the children of his adult children, were overly broad.
Strawbridge suggested they sought material beyond the scope of a lawful congressional inquiry and would result in banks turning over accounting of "every Diet Coke that a teenager bought using a credit card from Capital One."
He cautioned against a scenario in which the court might "rubber-stamp the broadest possible subpoena ever served on a sitting president."
The judges didn't rule Friday, saying they would deliver their decision at a later date.
This story has been updated.