On March 4, 2019, the House Judiciary Committee sent a letter to Hicks requesting information regarding alleged obstruction of justice by the current administration. (She was mentioned over 180 times in Robert Mueller's report on Russian election interference and possible obstruction of justice; the report was released on April 18, 2019. ) The Committee subpoenaed documents and her testimony on May 21, 2019. On June 4, 2019, the Trump White House invoked executive privilege, directing Hicks to not provide any documents related to her employment in the Trump administration. She agreed to testify in a closed-door session on June 19, 2019, during which lawyers for the Trump administration forbade Hicks from answering questions 155 times, claiming that due to "absolute immunity", Hicks "may not speak about anything that occurred during the time of her employment in the White House as a close adviser to the President". Hicks testified on the scheduled date, and also complied with the White House request to not answer questions.