Thomas' daughter, Jennifer Wright, told The Associated Press on Monday that Lisle and the juvenile were friends with her brother, but she said she was too upset to say much else.
"We're just beside ourselves," she said. "It's absolutely senseless."
Thomas was found dead early Sunday in the women's restroom at Smithville Lake, north of Kansas City, after one of the suspects told investigators where to find him, a Kansas City police detective wrote in a probable cause statement. His legs were bound with jumper cables, a green bag had been tied around his head and one of his fingers was partially severed.
While being interrogated, Lisle gave investigators a handwritten statement that said "the torture was senseless," adding that he and the juvenile shared a cigar after the victim gave up struggling, according to the police document.
No defense attorney was listed for Lisle in court documents, said Jim Roberts, spokesman for the Clay County prosecutor's office.