Updated at 6:39 p.m. on Wednesday, June 19, 2019, with more information.
The cellphone data from one of last week's four fatal overdose victims led police straight to her dealer's house, Hamilton County court records show.
Investigations into the three other fatal overdoses that took place between June 10 and June 11 are still underway, police spokeswoman Elisa Myzal said. No arrests have been made in any of those three.
In this case, police were called to the Microtel Inn, located at 7014 McCutcheon Road, on June 11, court records state. There they found a 33-year-old woman dead from a drug overdose. Police have not released her name, but on Facebook, friends and family publicly identified her as Heather Riley Walker.
Investigators searched the Walker's cellphone and found evidence of communication from the night before about a heroin deal between her and a person named "C.J.," later identified as 30-year-old James Shepheard, court records show.
It's not clear what that evidence was, though language used in court records suggests it was written communication. It was the last correspondence on the Walker's phone, court records state.
Police then found that a GPS map was loaded on the phone with directions to meet Shepheard at a house in the 6300 block of Jocelyn Drive.
In the meantime, the Hamilton County Medical Examiner's Office confirmed the cause of death to be an overdose of heroin.
Then on Tuesday, investigators set up surveillance outside Shepheard's house and stopped him as he left.
As police interviewed him, his phone "received numerous messages asking to purchase drugs," an investigator wrote in a criminal affidavit.
Shepheard admitted to setting up drug deals but said someone else used his phone to sell to Walker.
Regardless, police said Shepheard matched the description given by a witness at the scene of the death. That, coupled with the rest of the evidence, was enough to charge him with second-degree murder.
Shepheard was arrested Tuesday at 3:30 p.m. and booked into the Hamilton County Jail on Wednesday. His bond was set at $500,000, according to online jail records.
As for Walker, she was described as "a selfless loving mother, daughter and loyal friend who would go out her way to help others," according to her obituary.
In a post now shared 67 times, Walker's mother announced her daughter's death and asked for help finding the dealer.
" ... believe me justice will prevail because I'm not stopping until their brought to justice," she wrote.
A longtime friend of hers, Tiffany Ivey, said Walker was like a sister to her.
They grew up together, and Walker "had a smile that would light up the entire room," Ivey wrote in a message.
"She was the type of person to just come by at 9am to make my son and I chocolate chip pancakes just because she loved us," she said. "I cried so hard when i read on facebook that she was dead. Im still shocked ... This is definitely not the way she was supposed to leave this world. Rip beautiful Angel."
Shepheard is the second person to recently be charged with second-degree murder in connection to a fatal overdose.
Eric L. Williams Jr., 24, was arrested June 7 in connection to a May 6 fatal methamphetamine overdose.