Jewell was initially hailed a hero when he helped evacuate a busy area at the sporting extravaganza in Atlanta, Georgia, after finding a backpack containing a trio of explosive devices.
He was later mistakenly identified as a suspect, and although the guard was exonerated long before his death in 2007, Hamm was surprised to find that so many people still have their facts wrong.
"It was very weird being down in Atlanta shooting the film because people would ask, 'What are you working on?' and you'd say, 'The Richard Jewell Story,' and they'd go, 'Oh, the guy that bombed the Olympics?' And you're, like, 'No, no, no!' " he tells U.S. morning show "Live with Kelly and Ryan".
"And that's what the film hopefully tries to set straight, that historical record. And even though he (Jewell) was completely exonerated and never charged, (he) was put through the laundry cycle."
"It was kind of like a perfect storm of miscommunication which obviously we know can happen even faster and more devastating nowadays (sic). But this was 1996 in the hometown of CNN, so every single news organisation... was trying to be the first one to get there (to the news story), and in the rush to be first, they forgot... the truth."
The "Mad Men" star is still disappointed people's memories are so clouded, but hopes the film will help to create a new narrative.
"It's a bummer. It's one of those things where, if you're ever under that lens, you realise how much that can devastate your life," Hamm remarks. "And they (Jewell and his family) went through this for 88 days, the scrutiny, never being charged with a single thing. It wasn't just Richard, it was his mum. They had 2,000 journalists and people outside their apartment, waiting for them to go anywhere. They couldn't leave the house."
Jewell's mother attended the film's Atlanta premiere earlier this month and is delighted at how her son is depicted.
"She was so pleased," Hamm shares. "She's so pleased her son is being recognised as the hero that he was."