Utah prosecutors will seek the death penalty against the 22-year-old accused of shooting conservative activist Charlie Kirk and have disclosed text messages and other new details they say fueled the assassination plot.

The suspect, Tyler Robinson, was charged with aggravated murder in a 10-page criminal information on Sept. 16, setting the stage for a high-profile court proceeding in the months ahead.

Robinson faces seven felonies, including discharge of a firearm, obstruction of justice, and witness tampering for allegedly instructing his roommate not to cooperate with authorities.

Utah County Attorney Jeff Gray outlined the charges at a news conference and said authorities will seek the death penalty. Utah is one of 21 states that allow the death penalty.

Kirk's death strikes a "personal and intimate chord," Gray said.

"Charlie Kirk was first and foremost a husband and father to two beautiful children, a son, a brother and a friend," he said. "I am charged with bringing justice for Charlie Kirk."

Kirk, 31, whose hard-line conservative views inspired millions and infuriated millions of others, was shot to death Sept. 10 while speaking to students at Utah Valley University in Orem, Utah, as part of his "American Comeback Tour."

His death and the chaotic scene at the university prompted a 33-hour manhunt for his killer. Robinson turned himself in late on Sept. 11 near his home in St. George, Utah. He was initially held on charges of aggravated murder, obstructing justice and unlawfully discharging a firearm.

Gray said DNA consistent with Robinson's was found on the trigger of the rifle believed to have been used to kill Kirk, along with other parts of the rifle and shell casings. The FBI had announced earlier that Robinson’s DNA was found on a towel wrapped around the rifle and a screwdriver found on the roof where police say the fatal shot was fired.

Robinson could still face parallel federal charges if the state’s U.S. attorney pursues them.

New details emerge

Court documents revealed new details about Robinson's alleged planning of the shooting, motive and plan to escape the scene.

After the shooting, according to the court documents, Robinson messaged his live-in roommate, who he was dating, and said: "drop what you are doing, look under my keyboard."

The roommate looked under the keyboard and found a note that read, "I had the opportunity to take out Charlie Kirk and I'm going to take it," the documents say.

'Why did I do it?'

At the news conference, Gray read from a text message log between Robinson and the roommate:

Roommate: you weren’t the one who did it right????

Robinson: I am, I’m sorry

Roommate: I thought they caught the person?

Robinson: no, they grabbed some crazy old dude, then interrogated someone in similar clothing. I had planned to grab my rifle from my drop point shortly after, but most of that side of town got locked down. Its quiet, almost enough to get out, but theres one vehicle lingering.

Roommate: Why?

Robinson: Why did I do it?

Roommate: Yeah

Robinson: I had enough of his hatred. Some hate can’t be negotiated out. If I am able to grab my rifle unseen, I will have left no evidence. Going to attempt to retrieve it again, hopefully they have moved on. I haven’t seen anything about them finding it.…

Roommate: How long have you been planning this?

Robinson: a bit over a week I believe. I can get close to it but there is a squad car parked right by it. I think they already swept that spot, but I don’t wanna chance it

Robinson's mother saw a photo that authorities had released of the alleged shooter and though it could be her son, the court documents say. She called him, but he said he had been home sick.

"Robinson’s mother explained that over the last year or so, Robinson had become more political and had started to lean more to the left – becoming more pro-gay and trans-rights oriented," the court filing alleges.

Robinson's father also recognized his son and potentially the rifle he had gifted him. He asked his son to send him a photo, but instead the son said he was intending to take his own life.

"Robinson’s parents were able to convince him to meet at their home," the court document alleges. "When asked why he did it, Robinson explained there is too much evil and the guy [Charlie Kirk] spreads too much hate."

After meeting with his parents and a family friend, Robinson turned himself in to local authorities in Washington County late on Sept. 11.

This article originally appeared on USA TODAY: Suspect in Charlie Kirk shooting charged with aggravated murder, could face death penalty

Reporting by Nick Penzenstadler, USA TODAY / USA TODAY

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