Katelyn Markham's Murderer Kept Binders Filled With Handwritten Notes About Wanting to Kill Her

As cliched as it sounds, Katelyn Markham really did have her whole life ahead of her, and things were looking good. The 22-year-old was close to getting her graphic arts degree from the Art Institute of Ohio-Cincinnati, which would have led to the career of her dreams. On Aug. 13, 2011, the young artist was two days shy of her 23rd birthday and gearing up to celebrate a year of being engaged, when she disappeared, reported The Enquirer.

Markham's fiancé, John Carter, left her home between 11:30 p.m. and midnight that evening, but couldn't reach her at all the following day. Frantic, Carter called 911 around 8:00 p.m. on Aug. 14 to let them know that after letting himself into her apartment, there were no signs that Markham had been there since he saw her last. What happened to Katelyn Markham? Here's what we know.

Carter told police that his fiancée's car was still parked outside the apartment complex where she lived with her father. Strangely, Markham's dog had been locked in her bedroom, as if to make sure the pup couldn't get in the way of anything happening in the rest of the home.

A massive search for Markham was organized and included friends, family, and a national search group from Texas, per the Cincinnati Enquirer. According to CBS News, Markham's father, Dave Markham, offered a $5,000 reward for his daughter's return and even went on NBC's Today show to beg for any and all information surrounding her disappearance. Sadly, Markham's body was found in May 2013 by a couple searching for aluminum cans at Big Cedar Creek in Indiana — 20 miles from where Markham had vanished.

For the next 12 years, Dave would be left wondering what happened to his daughter. When he finally got an answer, it was shocking and unsettling. A search of the home where Carter lived more than 10 years after Markham's death yielded disturbing results.

In March 2023, Carter was charged with two counts of felony murder in connection with Markham's death. It was hard to believe Carter was responsible for her death, given how distraught he was when he called police to report she was missing. Carter told WCPO at the time that he "just want[ed] to find Katelyn and celebrate her birthday with her." He went on to say he was hopeful because she was such a strong fighter. It was quite the performance.

Days before Carter was taken into custody, his indictment was unsealed, revealing the evidence that led to his arrest. Butler County Prosecutor Michael Gmoser was forced to read some of it aloud in court. Search warrants were executed at the homes of people Carter knew, as well as at the Fairfield residence where he resided with his mother. Authorities also dug up the surrounding yards of these homes.

Police found binders filled with handwritten documents about what Carter wanted to do to his fiancée. He wrote about loving Markham but still wanting to kill her. It was if he was having a conversation with himself. In one note he said, "I slit your wrist with the key to your heart." The prosecution then "referenced a forensic anthropology report that indicates there was sharp instrumental trauma to Markham’s wrist," per WCPO.

A little over a year later, in July 2024, Carter was handed a three-year prison sentence, reported CBS News. Prior to his sentencing, Dave delivered an emotional victim impact statement. "Not a day goes by that I don't think of Katelyn," he said. "Let him feel the pain that many of us have endured for the past 13 years."