Outside the state district court where the preliminary hearing of a man charged with shooting Charlie Kirk was about to begin its first day, the Houston-based podcaster Keli Rabon laughed sheepishly when asked if that man, Tyler Robinson, was guilty.

“You’re going to think I’m crazy,” Ms. Rabon replied, “but I think Charlie’s still alive.”

Mr. Robinson, she went on, “was at most a spotter” at the scene of the crime at Utah Valley University last September. Ms. Rabon suggested that Mr. Kirk, a 31-year-old conservative activist, was currently at an undisclosed location and that he, along with his wife, President Trump and other government officials, were potentially involved in the “psy-op.”

Ms. Rabon is one of several conspiracy theorists at the Provo courthouse. Camping out overnight to be the first member of the public allowed into the courtroom, Selena Armitage, too, had questions. A true-crime enthusiast living 45 miles away in West Valley City, Ms. Armitage said of Mr. Kirk’s murder, “I don’t think we’ve even scratched the surface.”

The proceeding this week to weigh evidence against the accused will seek to impose judicial norms on a case that seems likely to test those standards to the breaking point. Mr. Kirk’s death, after all, is the first assassination of a prominent American political figure in the internet age. Any straightforward prosecution of Mr. Robinson will require navigating a parallel universe of conspiracy theories turbocharged by social media.

The cramped district courtroom has just 14 seats available to the public, and some will be occupied by people like Ms. Rabon and Ms. Armitage, who are of the view that the state’s case is far from the complete picture. They will be reinforced by untold watchers of the hearing’s livestream.

The shooting was, in effect, nationally televised. The moment a bullet pierced Mr. Kirk’s neck was captured on mobile phones and posted in real time.

As straightforward as the horrific footage was, internet sleuths were not taking it at face value: Where is the exit wound? Where is the blood? Who are the adults in the campus audience? Is one of them gesturing just before the shot? Why do some of the staff members of Turning Point USA, Mr. Kirk’s political organization, seem to react without alarm to his slumping body? Why are several men in the crowd wearing maroon shirts?

The first two days of testimony have offered additional fodder. The prosecution’s opening witness, a former Utah Valley special officer named Chris Bagley, testified on Monday that his body camera’s battery died while he was investigating the rooftop where the police say Mr. Robinson fired his lethal shot.

Under cross-examination by the defense attorney Kathryn Nester, Mr. Bagley also acknowledged that his report did not include any mention of a rifle case that surveillance video showed the shooter carrying. Nor had he identified a plainclothes officer with a badge who had accompanied Mr. Bagley to the rooftop. Nor had he secured an empty pistol holster that he saw lying abandoned on the grassy area near where Mr. Kirk was killed.

On Tuesday morning, Ms. Nester elicited from the lead investigator in the case, David Hull from the State Bureau of Investigation, the facts that no shell casings had been found on the rooftop, while at least two other firearms were discovered at the crime scene below. Mr. Hull also admitted that he had not interviewed two individuals who claimed that their own rooftop video featured an individual whose clothing and build did not match those of Mr. Robinson’s.

Such vagaries are common in criminal investigations. Evidence is rarely conclusive, eyewitness accounts seldom 100 percent reliable, confessions not always ironclad. But such nuance can be lost on the judges and juries of social media.

Right-wing social media influencers have foraged on Mr. Kirk’s assassination with particular zeal, chief among them Candace Owens, a former Turning Point USA star turned antagonist who has devoted dozens of podcast episodes to the subject.

“I feel confident stating that Tyler Robinson did not murder Charlie Kirk,” Ms. Owens said recently. In her view, Mr. Robinson was “a total patsy” who was not even on campus that day.

Ms. Owens has at various times implicated the murder victim’s widow, Erika Kirk, Turning Point USA staff, and even the Israeli government, but only with tantalizing questions and dots for her audience to connect, not a true alternative scenario.

Mrs. Kirk and other Turning Point officials have expressed outrage, but privately, they have acknowledged the far right’s susceptibility to such theories, owing to a suspicion of traditional news sources and hostility toward the left.

Mr. Kirk himself regularly argued that the 2020 presidential election was stolen and that Democrats were purposely opening the border to reshape the electorate.

Such theories may lack evidence, but they have an audience. By far the biggest media presence at the Utah preliminary hearing is Fox News Channel, which has more than a dozen employees in Provo. And as Ms. Rabon acknowledged outside the courtroom, conspiracy theories are popular — some more than others. Her podcast was eight months old and already had 7,500 YouTube subscribers, a figure that she said would be higher if she were to embrace a more alluring conspiracy theory, such as the belief that Mr. Kirk was killed by an incendiary device in his microphone.

“I’m doing ‘fake death,’” Ms. Rabon said. “If I was doing ‘exploding microphone,’ the algorithms would like me better.”