Donald Trump Jr. is being privately interviewed by members of the Senate Intelligence Committee on Wednesday.

Trump Jr.’s meeting comes after Chairman of the Senate Intelligence Committee, Sen. Richard Burr (R-North Carolina), subpoenaed him in order to force him to appear before the panel. Burr is following up on previous testimony from Trump Jr. According to a report from CNN, the president’s eldest son agreed to be questioned for up to four hours on a series of at most six different topics.

Some analysts believe that the Senate Intelligence Committee wants to question Trump Jr. on the validity of his previous statements, with reporters wondering whether he will have to “correct” any of his prior testimony. Trump Jr., who testified before the committee once before in 2017, was an instrumental figure in the 2016 Trump Tower meeting between senior Trump campaign officials and a Kremlin-connected lawyer. He was also heavily investigated by former special counsel Robert Mueller during his probe into Russian campaign interference, but the prosecutor found no evidence of collusion.

Many Republican senators were outraged at Burr’s actions, attacking him for calling in the child of the president to testify after Mueller’s investigation had already ended. However, even though the special counsel has concluded his investigation, the Senate Intelligence Committee’s inquiry is still ongoing. The probe, which is supposedly bipartisan, is nearly complete, but Burr said that there are still a handful of witnesses he needs to hear from, including Trump Jr. The committee wants to hear from the president’s son again because of discrepancies between his 2017 testimony and the testimony of others involved in the matter. While Trump Jr. originally claimed that he had only told Jared Kushner and former campaign manager Paul Manafort about the meeting ahead of time, testimony from then-campaign deputy Rick Gates told Mueller that Trump Jr. had mentioned the meeting during a larger campaign meeting.