The House Judiciary Committee on Tuesday issued subpoenas to President Trump’s former top staffer Hope Hicks and ex-White House counsel Donald McGahn’s chief of staff as part of its expansive probe into potential abuse of power, public corruption and obstruction.

The move to compel testimony from Hicks and Annie Donaldson comes one day after the White House blocked McGahn from testifying before the committee and the former counsel was a no-show at Tuesday morning’s hearing, ongoing defiance of congressional inquiries that has outraged Democrats and increased calls for impeachment.

Rep. Jerrold Nadler (D-N.Y.), chairman of the committee, issued the subpoenas, the panel said in a statement. The panel requested documents from Hicks and Donaldson by June 4, and they requested that Hicks testify on June 19 and Donaldson on June 24.

The committee, which voted to authorize the subpoenas weeks ago, is particularly interested in Donaldson, who took detailed notes of McGahn’s exchanges with the president. McGahn was a central witness in some of the 10 instances of potential obstruction identified by special counsel Robert S. Mueller III in his report.

The panel also believes Hicks, a longtime close confidant of Trump, probably knows details on several topics they are investigating.

It is unclear, however, if the two women will comply with the subpoenas — particularly after the White House earlier this month moved to block similarly subpoenaed document requests to McGahn. McGahn faced a deadline to hand over all communications pertaining to the Mueller probe, but the White House told McGahn it would invoke executive privilege over the material.

McGahn ultimately refused to turn over anything.

The White House is expected to do the same for both women, daring the Judiciary panel to hold all three former White House aides in contempt of Congress. Trump has refused to comply with the multiple congressional investigations while Republicans have insisted it is time for Democrats to end their probes and move on.

Democrats have threatened to hold former uncooperative aides in contempt, vowing to take individuals to civil court to try to convince a judge to force them to cooperate. They have also discussed fining aides who refuse to comply.

The Judiciary staff has been in contact with representatives for both Hicks and Donaldson. But following Trump’s move to block all aides from cooperating, panel Democrats felt they had to take a more aggressive move to force compliance.

They are particularly interested in Donaldson, who appears as a critical contemporaneous narrator of some of the most worrisome and tempestuous moments inside the West Wing. She took notes directly from McGahn as he left discussions with Trump, documenting how he railed against and sought to control a criminal investigation that he felt imperiled his presidency.

Donaldson is a sought-after witness because she can bring events in the White House to life, explaining what she and McGahn were feeling or fearing when Trump took some actions. They would seek her reactions to some of these moments, including when Trump announced to staff he would fire FBI director James B. Comey, and when he ordered McGahn to try to intervene and have Mueller removed for alleged conflicts of interest.

Donaldson’s daily habit of documenting conversations and meetings provided the special counsel’s office with its version of the Nixon White House tapes: a running account of the president’s actions, albeit in sentence fragments and concise descriptions.

Donaldson famously fretted in her West Wing diary “is this the beginning of the end?” when Trump insisted on firing Comey in May 2017 and on mentioning the president was not a subject of the Russia investigation in his public termination letter. She and McGahn both believed his mention of the Russia probe could be viewed as evidence he was engaged in obstruction of justice. She also described McGahn’s repeated efforts to try to protect Trump from his worst impulses and the case he was building against himself in various ways. That included when he sought to call the Justice Department himself and tried to improperly pressure Attorney General Jeff Sessions to “unrecuse” and resume control over the investigation.

Donaldson, 37, is married to a former Justice Department lawyer, and the couple has returned to Alabama. She is described by friends as proud of her work helping to implement a conservative agenda, but somewhat stung by her experience in Washington.

The panel has sought to talk to Hicks as well. In an early March letter, they asked her to turn over communications she has had related to dozens of topics: They wanted any information about former national security adviser Michael Flynn’s move to lie to the FBI about his contacts with Russian official Sergey Kislyak as well as his resignation. They have asked for any information she has on Trump’s contact with Comey, particularly his firing.

They also asked her about hush payments to women alleging affairs with the president during the 2016 election and the June 9, 2016 Trump Tower meeting involving Donald Trump Jr., Paul Manafort, Jared Kushner and Russians who offered dirt on Hillary Clinton. Hicks was reportedly involved in crafting a July 8, 2017 statement about that meeting that was later found inaccurate.