John Carter pleads guilty to involuntary manslaughter in 2011 killing of Katelyn Markham

John Carter, Katelyn Markham’s fiancé who faced two murder charges in connection to her 2011 death, pleaded guilty to involuntary manslaughter in a Butler County courtroom Friday morning.

Carter’s attorneys entered the plea before Butler County Common Pleas Court Judge Daniel Haughey, acknowledging that he caused Markham's death in the course of committing a misdemeanor assault.

Carter, 36, was accused in 2023 of killing his fiancée. He initially pleaded not guilty and has since remained free on a $1 million bond.

"The guilty plea by the defendant, John Carter, concludes the investigative work of a number of law enforcement agencies, my office and other investigative professionals, and brings absolute undeniable finality to the question of 'Who is responsible and accountable for the disappearance and death of Katelyn Markham?'" said Butler County Prosecutor Michael Gmoser.

Prosecutors said her family was advised of and are in agreement with the plea negotiations. Dave Markham, Katelyn Markham's father, was present in the courtroom Friday but declined to speak about the case after the hearing. A memorial event is planned for Saturday at Creekside Park in Fairfield.

What happened to Katelyn Markham?

Markham disappeared on Aug. 13, 2011. She was last seen between 11:30 p.m. and midnight when Carter said he left her Dorshire Drive home

Friends, relatives, local authorities and a national mounted search group from Texas conducted dozens of searches for Markham. They combed local parks, waterways and areas in Butler and Hamilton counties but found no sign of her.

It was Carter who called 911 on April 14, saying he could not reach Markham throughout the day. He told Fairfield police that he let himself into Markham's townhouse and found no signs of her. Her purse and keys were inside but her cell phone was missing. Markham's car was parked outside and her dog wasn't locked up, Carter said.

When Markham disappeared, she was a month away from finishing her graphic arts degree at the Art Institute of Ohio-Cincinnati. She also was nearing the first anniversary of her engagement to Carter.

Carter said he and Markham were planning to move to Colorado that November. However, several witnesses told investigators Carter and Markham's relationship had become strained in the months leading up to her disappearance, according to court filings.

Markham even confided in one witness that she was unhappy with her engagement to Carter and she felt "trapped in the relationship."

Where was she found?

Markham’s remains were found nearly two years later, on April 7, 2013, in a rural, wooded area at Big Cedar Creek in southeastern Indiana’s Cedar Grove. A couple looking for scrap metal spotted a human jaw in a plastic grocery bag.

Her death was ruled a homicide, but her cause of death has not been established.

Prosecutor: Evidence against Carter largely "circumstantial"

The case lacked any evidence that viewers of crime dramas might expect in a murder trial, including DNA or fingerprints, Gmoser said.

"As such, this case presented the most extensive and challenging collection of circumstantial evidence never before seen in this office to reach the guilty plea today and end the dissembling of the defendant, and his alibi, that have gone on for way too long," Gmoser said in court.

During Carter's March 2023 arraignment, Gmoser offered examples of evidence prosecutors planned to present at trial. Those included cryptic writings belonging to Carter, which were recovered during the execution of a search warrant at his former residence.

When police interviewed Carter the day after Markham's disappearance, investigators observed and photographed scratch marks on the left side of his neck, according to a search warrant unsealed ahead of trial. He initially said the scratches came from a razor but later told police he didn't know how he got them.

Markham's remains showed cutting wounds caused by "sharp force trauma" to her left wrist, according to prosecutors, who said Carter caused her death by "physical violence and by force."

Three polygraph examinations indicated "deceptive responses" from Carter as he denied his involvement in Markham's death, according to investigators.

Investigators believe Carter obtained plastic sheeting − typically used in construction and landscaping − and used the material to dispose of Markham's corpse, the search warrant states.

Markham's remains were found wrapped in that same type of material, though her skull had been wrapped separately, the documents said.

Carter would have been familiar with the area where Markham's remains were recovered, the search warrant said, because it was near the routes from his home in Butler County to the properties his father owned in Ross Township and Laurel, Indiana.

A forensic anthropology report indicated that the location where Markham's remains were discovered is different from where they were first left.

His jury trial was set to begin June 24 and was expected to last five weeks. Carter is facing a maximum possible sentence of three years in prison. He's scheduled to appear in court for sentencing on July 18.

This article originally appeared on Cincinnati Enquirer: John Carter pleads to lesser charge in fiancee Katelyn Markham's death