A Riverton man, who police say shot and killed his 35-year-old brother last weekend after a day of arguing, was released from jail Thursday.

The Salt Lake County Jail received a no-complaint order Thursday afternoon, allowing Steven Shane Knighton, 39, to be released from the jail, where he had been held since the shooting in the early morning hours of Saturday.

Alicia Cook, a spokeswoman for the Salt Lake County District Attorney's Office, said prosecutors had asked the Salt Lake County Sheriff's Office to continue the investigation and bring them more evidence before they decide if any criminal charges will be filed against Knighton.

"We can only hold an individual for a certain amount of time, and it is our assessment that the investigation will not be complete by that time," Cook said.

Cook would not discuss specifics about the case, saying only that there are some "questions that we think need to be addressed."

The sheriff's office said Knighton and his brother Shad Michael Knighton had been together all day Friday moving items between storage sheds. An argument between the men escalated throughout the day, and by late Friday, early Saturday, Shad Knighton was becoming physically aggressive, walking up and down the street ranting and raving, police said.

At some point, Shad Knighton broke a window in a neighbor's parked car then threw either a cell phone or a wrench at a passing driver, Salt Lake County Sheriff's Lt. Don Hutson said.

Later in the night, Steven Knighton became concerned that his brother was becoming violent, and he got a handgun and at some point made a decision that he needed to use lethal force, so he shot and killed his brother, said Hutson.

Police arrived at the scene at 1:53 a.m. — about five minutes after neighbors say they heard gunshots.

Before shots were fired, police say there was a physical altercation between Shad Knighton and Steven Knighton's wife in the entryway of the home at 2458 W. 12875 South. Police said Shad Knighton's roommate also had been at the home and had angered the man.

After firing several shots, Steven Knighton then called police and reported that he had shot his brother, Hutson said. He waited at the house and tried to administer CPR to his brother until officers arrived.

Shad Knighton, who was shot twice in the chest, was declared dead at the scene. Steven Knighton surrendered without incident and was cooperative with police.

"The district attorney's office wants to make sure it is a thorough investigation," Hutson said. "They don't think it is critical to push through quickly because they don't believe he is a flight risk, he has been cooperative and they don't think he is a danger to himself or the public."

Knighton was released from the jail just before 3:30 p.m.

Hutson did say that just because charges are not filed right now does not mean that they couldn't be in the future. If charges are filed, a warrant would be issued for Knighton's arrest.

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