House Oversight and Accountability Chairman James Comer, R-Ky., subpoenaed the embattled head of the Secret Service on Wednesday for a hearing about security failures that occurred before the attempted assassination of former President Donald Trump on Saturday. 

U.S. Secret Service Director Kimberly Cheatle has said that the buck stops with her but said she is not resigning. 

The Oversight Committee subpoena calls for Cheatle to come to a hearing at 10 a.m. on July 22. 

“The assassination attempt of the former president and current Republican nominee for president represents a total failure of the agency’s core mission and demands congressional oversight,” says a letter from Comer to Cheatle.  

“Despite allowing you to speak with the media, both the U.S. Department of Homeland Security (DHS) and the Secret Service have failed to provide assurances regarding your appearance at the Oversight Committee’s scheduled hearing, thereby necessitating the attached subpoena,” the letter continues. 

During the Saturday Trump rally in Butler, Pennsylvania, a gunman fired an AR-style rifle at the former president, hitting his ear, killing a spectator, and injuring two others in the crowd. 

The subpoena comes one day after House Speaker Mike Johnson, R-La., said the House would conduct a “thorough investigation” of the security failures.

On Thursday, Johnson told The Daily Signal that he is calling on Cheatle to resign and said he would set up a special task force to investigate the assassination attempt

The Comer letter notes the Department of Homeland Security has stonewalled the committee: “Initially, the Secret Service committed to your attendance. Subsequently, however, DHS officials appear to have intervened, and your attendance is now in question.” 

“In addition, since DHS’s intervention, there have been no meaningful updates or information shared with the committee,” Comer added. “The lack of transparency and failure to cooperate with the committee on this pressing matter by both DHS and the Secret Service further calls into question your ability to lead the Secret Service and necessitates the attached subpoena compelling your appearance before the Oversight Committee.”