The House select committee investigating the Jan. 6 Capitol attack has spoken with Marc Short, former Vice President Mike Pence’s chief of staff, CNN reports.

Short testified before the committee last Wednesday, after receiving a subpoena, people with knowledge of the matter told CNN. The panel is looking at all facets of how the attack came to be, including former President Donald Trump’s actions before and during the riot. Short was at a White House meeting on Jan. 4, 2021, when Trump and attorney John Eastman attempted to coerce Pence into overturning the election results, and he also accompanied Pence to the Capitol on Jan. 6.

Before he testified, Short had turned over some documents that had been subpoenaed by the committee, including a memo from Trump aide Johnny McEntee that compared Trump to Thomas Jefferson, a person familiar with the matter told CNN. It is still unclear if Pence himself will appear before the committee; the panel has been in contact with his legal team, but people close to Pence told CNN he would rather have a “proxy” like Short cooperate in his place.

This weekend, Trump released a statement denouncing Pence, falsely claiming, “He could have overturned the election!” A person close to Pence told CNN that the former vice president may respond to Trump later this week when he speaks at a Federalist Society gathering in Florida.