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Senator Ron Johnson has sent two letters to acting U.S. Capitol Police chief that appeared to cast doubt on the official accounts that said Officer Brian Sicknick’s death was related to the January 6 attack on the Capitol, leading to a war of words with the department. The Capitol police responded that they shared his “dismay that our officer’s death may be used for political purposes,” leading Johnson to respond that they “failed to address the majority of the questions in my letter.”

In the first letter, which was sent on April 22 and obtained by CBS News, the Wisconsin Republican demanded answers about “misinformation” and “false reports” surrounding Sicknick’s death. 

“The recent medical examiner ruling Sicknick ‘died of natural causes’ raises questions regarding the USCP’s press release on January 7, 2021, that stated Officer Sicknick died from ‘injuries sustained while on-duty’ after physically engaging with protesters at the U.S. Capitol on January 6, 2021,” Johnson’s letter said.

When the Capitol police announced Sicknick’s death on January 7, they said he had died he died from “injuries sustained while on-duty.” But the D.C. medical examiner’s office said on April 19 that Sicknick died from strokes, citing “acute brainstem and cerebellar infarcts due to acute basilar artery thrombosis.” 

Officer Brian Sicknick

United States Capitol Police via AP

In an interview with The Washington Post, chief medical examiner Francisco J. Diaz said Sicknick suffered two strokes at the base of his brainstem caused by a clot in an artery.  At approximately 2:20 p.m. on January 6, Sicknick was sprayed with a chemical substance outside the Capitol, the office said. He collapsed eight hours later and died the following evening. 

Julian Khater and George Tanios were arrested for the attack on Sicknick and two other police officers. 

There were initial reports that Sicknick was struck with a fire extinguisher, which Democratic House impeachment managers cited during former President Trump’s impeachment trial

“The death of any police officer is a tragedy and the use of any officer’s death for political purposes or to create a false narrative is reprehensible and disrespectful to the officer’s family and the officer’s memory,” Johnson wrote.

A spokesman for the U.S. Capitol Police told CBS News via email they will not comment on the Senator’s letter, “The Department is staying out of the political debate. It is the USCP’s longstanding policy to stay out of politics.”

The USCP sent a one-page response on May 6, provided to CBS News by Johnson. The agency noted that due to the criminal investigation and ongoing prosecutions, they are “limited in what our Department can provide.” But USCP General Counsel Thomas DiBiase also appeared to take issue with Johnson’s criticism of their January 7 public comments.

“Indeed, the DCOCME [DC Office of the Chief Medical Examiner] conclusion does not mean that Office Sicknick was not assaulted nor that the events at the Capitol did not contribute to his death,” DiBlase wrote. 

He said the department did not put out a release that Sicknick was assaulted by a fire extinguisher and said he’s not aware of any communication between USCP and House Impeachment Managers on the issue of Sicknick’s death.

DiBiase ended the response by saying that he shares “your dismay that our officer’s death may be used for political purposes.”

Johnson sent a follow-up letter on May 13 calling the USCP response “incomplete,” and saying it “failed to address the majority of the questions in my letter.”

Johnson said the USCP’s answer “This is not a legitimate justification for refusing to respond to questions that do not appear to be materially related to the criminal case against the two defendants charged with assaulting Officer Sicknick.”

He then reasked the list of the questions from the first letter.

Johnson, who has sought to minimize the attack on the Capitol, asked the Capitol Police to provide a full timeline and description of Sicknick’s work activities on January 6 up until his death. He is also seeking more information on why the agency said on January 7 that he died due to injuries sustained while on duty; details on claims of misinformation, including that Sicknick was struck with a fire extinguisher; what information has been shared with the Sicknick family about his death; if House impeachment managers contacted the USCP regarding the officer’s death; what information was provided to the FBI; and if the department has sought an investigation into how the January 7 release was developed and approved. 

On Thursday, Johnson met with Sicknick’s mother, Gladys Sicknick, and the senator said in a statement that  “words cannot adequately express my sympathy for their loss…I did commit to doing everything I could to ensure all their questions will be answered.”

Gladys Sicknick said during the meeting, she told Johnson, “just look at the footage of what all these people went through and all these police officers to make them safe to keep them safe.”