A source told CNN on Monday that the former vice president's ex-chief of staff is complying with the congressional panel's investigation into the January 6 insurrection.
The attack on the US Capitol and events on January 6 itself could be given testimony by the aide to the vice president.
Insider previously reported that Short was critical of the legally dubious effort to have Vice President Mike Pence block the certification of President Joe Biden's victory in the 2020 election.
The plan was described as a "proposed coup" by a constitutional law expert. Short called it "boneheaded analysis".
He invoked his 5th amendment right to remain silent when he refused to comply with the investigation by the House select committee.
On January 6 a mob of Donald Trump's supporters went to Congress to try to block Biden's victory, and some of them demanded that Pence be executed for declining to do so himself.
Trump barred Short from the White House after the attack.
A person for the committee did not respond to the request for comment.
