The Republican-led Senate Intelligence Committee has subpoenaed Donald Trump Jr. to appear for additional questioning as it continues its investigation into Russian interference in the 2016 presidential election. The subpoena is notable because it comes from a Republican committee chair, Sen. Richard Burr (R-N.C.), and runs counter to the GOP messaging consensus on all things Russia-related post-Mueller—nothing to see here, time to move on. The subpoena is thought to be the first of a Trump family member; talks to have Trump Jr. appear again before the committee reportedly began before the Mueller report’s release, which could indicate that the appearance is not the result of new information from the report.

The exact motive behind compelling Trump Jr.’s testimony isn’t totally clear. The committee is bringing back several witnesses for second interviews as the investigation reaches its conclusion, but the fact that Trump Jr. was subpoenaed indicates he likely refused to testify voluntarily. This jibes with the Trump administration’s stance writ large, as it has essentially refused to cooperate with congressional investigations of any kind, on any topic. The intel committee, however, is run by Republicans in the majority and could make it awkward for Trump Jr. to refuse to comply with the subpoena.

The president’s eldest son has been a key figure in a number of investigations into the 2016 election, including the Mueller investigation. Congressional Democrats say Trump Jr. likely perjured himself during previous testimony in how he represented his role in the June 2016 meeting at Trump Tower with a Russian lawyer claiming to have politically damaging information about Hillary Clinton. Burr, however, suggested in an interview with the Washington Post Tuesday that even if Trump Jr. was found to have misrepresented himself before the committee, he was not inclined to pursue perjury proceedings because Mueller had already passed on charging Trump Jr.*

“The special counsel, in the final redacted report released last month, said Trump Jr., Jared Kushner and Paul Manafort—the other senior Trump campaign officials in the meeting—didn’t face charges because his investigators lacked evidence to prove they took the meeting with the general knowledge they might ultimately be committing a crime,” Politico reports. “The Mueller report also includes a mysterious redaction that hides the fallout from Trump Jr.’s refusal to participate in a voluntary interview with the special counsel. The blacked-out section has set off speculation Mueller tried to subpoena Trump Jr., or the president’s son invoked his Fifth Amendment right against self-incrimination.”