Now Congress faces a very hard question: Subpoena President Donald Trump’s translator, or not?

On Saturday, The Washington Post’s Greg Miller reported new details of the extreme things done by Trump to conceal his talks with Russian President Vladimir Putin from even the senior-most members of Trump’s own administration. Trump even reportedly seized the interpreter’s notes after one of his meetings, the Trump-Putin sit-down at the Hamburg G20 meeting in July 2017. Even more disturbingly, Trump and Putin met privately a second time at Hamburg—with no American present. In an act of astonishing recklessness, Trump relied entirely on the Russian interpreter, preventing any U.S. record-keeping at all.

All this would be unusual enough for any president. It is more than suspicious for a president being formally investigated by the FBI as a possible Russian-intelligence asset.

Read: The strange, high-pressure work of presidential interpreters

Concern focuses most on Trump’s meetings with Putin at the Helsinki summit in July 2018. The Russian president, and the American president helped into office by the Russian president, met for two hours with no aides. No agenda was published before the meeting, no communiqué issued afterward. The Russian side later claimed that a number of agreements had been reached at the summit. Nobody on the American side seemed to know whether this was true. At a press conference four days after the meeting, Director of National Intelligence Dan Coats said, “I’m not in a position to either understand fully or talk about what happened in Helsinki.”