Jeremy Boshears, 32, of the 400-block of East 3rd Street in Coal City, Illinois, has been charged with one count of concealing a homicide. Bond was set at $250,000.
The Will County Sheriff's Office also issued a warrant Friday of Boshears. Charges have not yet been filed and are expected over the weekend.
Kearns, 24, was reported missing Tuesday after she failed to show up at her job at Café Miele in Orland Park. She was last seen around 1:30 a.m. Monday at Woody's Bar in Joliet, where she worked. Her shift had ended at midnight.
Police located Kearns' 1996 Jeep Grand Cherokee in a pole barn in Aroma Park Township Thursday. Her body was discovered in the back of the SUV. She died of a single gunshot wound to the head and her death was ruled a homicide, Kankakee County Coroner Bob Gessner said.
According to authorities, Kearns met Boshears four weeks ago while working at Woody's Bar. The pair began dating two weeks ago.
"She was a wonderful, wonderful girl, something like this should have never happened to her," said Kevin Kearns, the victim's father.
Kevin Kearns wants swift justice for his daughter. He spoke publicly for the first time since his daughter was found dead and said he was hopeful the case will wrap up soon.
"I have a lot of confidence in the investigator that's on case right now," said Kearns.
"Now that they are filing some kind of charges, I'm hopeful that it gives me a little bit more peace that there will be justice for my best friend," said Marie Roche, the victim's best friend.
Marie Roche, Katie's best friend, met Boshears for the first time on Sunday night at Woody's.
Roche thought Kearns was headed home after her shift on Sunday night, but police said she told other friends she was headed to nearby Outlaws, a biker clubhouse where Boshears hung out. Kearns was never heard from again.
"How? Why? What kind of cruel monster are you, what sick twisted mind do you have that you could have done to someone so sweet and so innocent," said Roche.
Her father can't begin to comprehend how someone could take the life of a daughter he describes as the light of his life.
"It's a very surreal situation you never expect anything like this to happen to you," Kevin Kearns said.
Thursday evening Kearns' family held a vigil outside Woody's bar, giving her a tearful farewell.
"Tonight's not about what happened. Tonight's about the memory of my sister. It's about the memory of Katie Kearns," Matt Kearns, her brother, said.
"She lit up the room. When she was in the room, you knew it. And she didn't even have to talk," said Tim Kearns, the victim's uncle.
"She reached people. She got to people. She got to people's hearts, and she meant a lot to all of us," said Daniel Brandt, friend.
Kearns lived with her family in Mokena. She was one of four children in a very close-knit family. Her mother passed away 10 years ago.