Who suffers when online sleuths turn true crime into entertainment?

Darin Dunkin was mourning his best friend, Brent Kopacka, when he first saw it – a barrage of online posts falsely claiming Kopacka was somehow tied to the November slayings of four college students in Moscow, Idaho.

"I started to defend him immediately, because I was shocked, and I was mad," Dunkin said in an interview with "Impact x Nightline." "I was really mad. And I should have let it go and let all these people just talk and run themselves into the ground. But I figured, well, maybe I can put a stop to it. But then I realized I'm just the one person against all these people on the internet."

On Nov. 13, 2022, Kaylee Goncalves, Maddie Mogen, Xana Kernodle and Ethan Chapin were stabbed to death in the middle of the night at their off-campus home at the University of Idaho. As the town reeled in its grief, it was also hit by a storm of misinformation and lies from online sleuths who decided to take the investigation into their own hands.

"You have this period of time where the police are doing their investigation, working through the evidence and trying to find and apprehend the perpetrator. And meanwhile, TikTok is running rampant with every theory, every possible speculation about the case. And this is creating a lot of chaos within the community," said Adam Golub, an American Studies professor at California State University, Fullerton who studies the link between true crime and entertainment.

University of Idaho students Haadiya Tariq, Daniel Ramirez and Ben DeWitt also spoke to "Impact" about the flood of false rumors and allegations that began circling online as they covered the case for their school paper, The Argonaut. Tariq and Ramirez graduated in May.

"It's an interesting question to ask people: How many people do you personally know who are accused of being the murderer? I know two," Tariq said.

"There was so many fingers pointed at so many people, and it was equally harmful where their full names were being put out on social media," Tariq said.

If internet sleuths point to the wrong person, "just the accusation alone of being involved in a quadruple murder of university students can damage a person's reputation beyond repair," said ABC News legal expert Brian Buckmire.

The false speculation about Kopacka's involvement in the murders was brought up by a caller on a YouTube and podcast show and also circulated far beyond that — to Facebook, Reddit and other social media platforms.

Dunkin, who had been friends with Kopacka since high school, was devastated to see Kopacka's name falsely tied to the crime just weeks after he died.

"It was just all this stuff that was not true at all. And it's all said by people who don't know him, never even met him," Dunkin told "Impact."

What actually happened to Kopacka was something Dunkin says was tough for him to come to terms with.

According to investigators, officers responded to Kopacka's Washington home on Dec. 15 after reports that he had threatened his roommates. The home was just miles away from the Idaho murders' crime scene. Kopacka barricaded himself for hours and at one point fired a gun. Police say they fired back and fatally shot Kopacka.

In Kopacka's obituary, his family said he had battled PTSD for years after returning home from serving in Afghanistan. Dunkin says Kopacka wasn't the same when he came back.

"He was more standoffish. He was more quiet and he became really private out of nowhere. He liked to move around a lot, and he had terrible crowd anxiety," Dunkin said.

"Impact" reached out to Kopacka's family for comment but did not hear back.

Meanwhile, for many in the Moscow, Idaho, community, the online frenzy clouded what should have been at the center of the story – the victims and the lives lost. It may have also bogged down investigators, according to Buckmire.

"They can clog up the process of investigating when you're looking for tips and facts about a case. Getting ten can be helpful. Getting a thousand, when 999 of them are just random people saying, 'I think this' — the police have to go through each and every one of them, and so it can delay an investigation," Buckmire said.

The Moscow police continuously pushed back against a flurry of false allegations throughout the investigation and even added a "rumor control" section to their website.

"The best thing people can do to help is to stop with any kind of rumors and just seek official information that comes out of the Moscow Police Department," Col. Kedrick Wills said in a Nov. 20 press conference.

On December 30, 2022 detectives arrested 28-year old Bryan Christopher Kohberger in Albrightsville, Pennsylvania, for four counts of first-degree murder and one count of burglary. The former criminology student at nearby Washington State University was arraigned on May 22. Kohberger's attorney told the judge her client would be "standing silent," prompting the judge to enter a not guilty plea on his behalf. The trial is set to begin in October.

Many questions still remain surrounding the murders of Kaylee Goncalves, Maddie Mogen, Xana Kernodle and Ethan Chapin, but one thing is for certain – America's obsession with true crime extends far beyond Moscow. In recent years, true crime has become a thriving industry.

"We now live in an age of true crime on demand," Golub said. "We essentially have true crime at our fingertips. You have podcasts, you have streaming documentaries. You now have, you know, YouTube and TikTok accounts that are generating true crime."

"I think people just have this sick fascination with true crime," Tariq said. "I think we all, in a sense, do."

The latest "Impact x Nightline" begins streaming Thursday, June 8 on Hulu. The producers are ABC News' Rachel Rosenbaum, Rachel Wenzlaff, Caroline Pahl, Lauren DiMundo and Zach Fannin.