5 things to know about Charlie Kirk murder suspect Tyler Robinson

5. Trans-identifying roommate cooperating with police, but suspect is not 

Utah Gov. Spencer Cox told NBC News' "Meet the Press" on Sunday that Tyler Robinson was in a romantic relationship with his trans-identifying roommate, confirming an earlier report from Fox News on the suspect. 

The Republican governor said that the roommate, who has been identified as 22-year-old Lance Twiggs, is a man who is "transitioning from male to female," and that the individual is cooperating with investigators. Investigators are still working to understand if the relationship played a part in the murder of Charlie Kirk, the official said. 

"What we have learned specifically is that this person did not have any knowledge, was shocked when they found out about it," Cox said about the roommate. 

While the Utah governor confirmed that the roommate is cooperating with authorities, Cox said that Robinson is not. Cox told NBC News that Robinson has invoked his Fifth Amendment rights, which gives him the right to remain silent. 

Six sources familiar with the investigation told Axios that authorities are trying to determine whether Robinson thought that Kirk's views on trans-identifying people were "hateful."

Investigators believe that the suspect's feelings about the Turning Point USA founder's views may help establish a motive for the killing.