AUGUSTA — An Augusta man accused of delivering a knockout punch, then kicking a man who later died of his injuries, pleaded not guilty to manslaughter Friday.

Warren Sidelinger

Warren L. Sidelinger, 42, of Augusta pleaded not guilty to a Class A manslaughter charge, which is punishable by up to 30 years in prison, in connection with the death of Joseph McKenna, also of Augusta.

Sidelinger, appearing Friday at the Capital Judicial Center via video from Kennebec County jail, is accused of  punching out McKenna, who subsequently hit his head on pavement and died two weeks later from his injuries.

McKenna, 57, died July 30 at Maine Medical Center in Portland due to injuries he suffered in a July 18 attack by Sidelinger, according to an affidavit filed by Christopher Roy, an investigator with Maine State Police.

Sidelinger confessed he had assaulted McKenna, according to Roy’s affidavit. He told Augusta Detective Michael Unterkoefler that McKenna did something inappropriate with his niece, but did not provide details about what McKenna allegedly did, or identify his niece. He told police he had seen McKenna earlier on the day of the assault, at the soup kitchen, and told him he was “on my list.”

Later that day, Sidelinger told police, he was walking on Water Street when he saw McKenna, and decided he was going to assault him.

Witnesses told police that Sidelinger punched McKenna, causing him to fall to the ground, and said the sound of McKenna’s head hitting the tar made a loud popping noise. One witness said they heard Sidelinger yell something about what McKenna owed him.

Video recordings from a Water Street apartment building were reviewed by police. The video, Roy wrote, shows a man later identified as Sidelinger approach McKenna and strike him in the face with what appeared to be a closed fist.

“The suspect appeared to punch Joseph with a significant amount of force, as your affiant observed the suspect winding up and using his momentum to punch Joseph in his facial area,” Roy’s affidavit states. “Joseph immediately falls backwards into the roadway striking the back of his head on the pavement. While Joseph is lying on his back, mostly motionless and likely unconscious, the suspect stands over him, bends forward at his waist and appears to yell at him. The male then uses his right foot/sneaker to strike/kick Joseph on the right side of his head/face.”

McKenna was taken to MaineGeneral Medical Center in Augusta with head injuries, then taken by LifeFlight of Maine helicopter to Maine Medical Center in Portland.

An autopsy conducted by the state’s deputy chief medical examiner, Dr. Liam Funte, determined the cause of death to be blunt force trauma and the manner of death as homicide.

Judge Daniel Mitchell rejected a request from John Pelletier, Sidelinger’s attorney, to lower his bail from the previously set $15,000, to $2,500.

Pelletier offered that Sidelinger, who in the past has struggled with substance abuse and been unhoused, could stay at his brother’s house in Gardiner, as a condition of the lower bail amount, and added that Sidelinger’s mother, who attended Friday’s court hearing, was also local and part of Sidelinger’s support network.

Kate Bozeman, an assistant attorney general, successfully argued that Sidelinger’s bail should remain at $15,000, noting the seriousness of the crime of which he is accused.

“The allegations are the defendant essentially beat a man to death, including striking him and kicking him … while he lay on the ground,” Bozeman said. “The defendant didn’t appear at all remorseful and seemed visibly upset the victim, in his view, pressed charges.”

McKenna’s obituary describes him as a very genuine person who enjoyed spending time with family and friends, taking walks and listening to music, and loved animals.

Sidelinger was taken into custody July 20 after authorities, who had recognized him on the video surveillance footage, found him walking. He had an apparent injury to his hand at the time.

His case is scheduled for a dispositional conference Dec. 13.