The President's real-time tweets attacking ex-Ambassador Marie Yovanovitch drew complaints from Democrats about witness intimidation, the President's Sunday Twitter shot at Williams had the same result.
Williams is scheduled to testify before the House Intelligence Committee on Tuesday morning, along with National Security Council staffer, Army Lt. Col. Alexander Vindman.
It's an extremely busy week for the impeachment hearings, as Democrats try to cram a series of witnesses into sessions on Tuesday, Wednesday, and Thursday.
The highlights include testimony from U.S. Ambassador to the European Union, Gordon Sondland, on Wednesday morning - Sondland has been the focus of a number of recent revelations focusing on his communications with the President about getting Ukraine to start investigations of the son of former Vice President Biden, and about questions of whether Ukraine - and not Russia - hacked Democrats in 2016.
Sondland's testimony on Wednesday morning is has become maybe the biggest item on the schedule this week.
Here is this week's announced schedule:
Tuesday morning: Pence foreign policy aide Jennifer Williams, and National Security Council staffer Army Lt. Col. Alexander Vindman.
Tuesday afternoon: Former US envoy to Ukraine Kurt Volker, and National Security Council staffer Tim Morrison.
Wednesday morning: US Ambassador to the European Union Gordon Sondland.
Wednesday afternoon: Pentagon official Laura Cooper, State Department official David Hale.
Thursday: Former Trump White House Russia expert Fiona Hill.