Lawmakers have apparently been poring over Special Counsel Robert Mueller’s report since it was released on Thursday. On Friday, Sen. Mitt Romney (R-UT), for one, concluded (falsely) that Trump had essentially been cleared of criminal wrongdoing, though he scathingly said he was “sickened” by Trump’s conduct.

Sen. Elizabeth Warren (D-MA), on the other hand, joined the growing calls for impeachment.

“The severity of this misconduct demands that elected officials in both parties set aside political considerations and do their constitutional duty,” Warren said in a tweetstorm. “That means the House should initiate impeachment proceedings against the President of the United States.”

As one of the top-tier presidential candidates on the Democratic side and a senator who would eventually oversee any impeachment trial, Warren’s decision was particularly notable.

“The Mueller report lays out facts showing that a hostile foreign government attacked our 2016 election to help Donald Trump and Donald Trump welcomed that help. Once elected, Donald Trump obstructed the investigation into that attack,” she said. “Mueller put the next step in the hands of Congress: ‘Congress has authority to prohibit a President’s corrupt use of his authority in order to protect the integrity of the administration of justice.’ The correct process for exercising that authority is impeachment.”

She added: