Washington (CNN) House Democrats are well within their authority to subpoena President Donald Trump's financial papers, House lawyers told the Supreme Court on Thursday.

As soon as Friday, the justices could decide whether to allow a subpoena to Trump's long time accounting firm to go forward, while they consider whether to take up the president's appeal in the case.

The documents include eight years of financial records from both before and during his presidency.

Lower courts have sided against the President, who made the emergency appeal to the Supreme Court to block the release of the records.

Thursday, House General Counsel Douglas Letter said in a court filing that Congress has broad investigative power.

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