NEOSHO, Mo. — After 34 years in law enforcement, Newton County Sheriff Ken Copeland has announced that he plans to retire and will not seek re-election.

Copeland, who worked for 17 years with the Joplin Police Department before going to the Newton County Sheriff's Department, says he plans to retire on Dec. 31 at the end of his current term.

Copeland, who will have served three terms as sheriff when he retires, has overseen upgrades to the Newton County Jail as well as a new radio system for the county that was installed three years ago.

He said working to maintain a professional department was always among his priorities, as was serving the residents of Newton County.

"I'm now going to make more time for my family," he told the Globe in a phone interview. "But I have enjoyed my time in law enforcement."

Copeland, who said he has worked a number of homicides during his career, said he was most personally affected by the abduction, rape and strangulation of 9-year-old Rowan Ford in November 2007.

Christopher Collings, of Wheaton, has been sentenced to death in connection with the crime. Investigators said Rowan was taken from her home in Stella to Collings' trailer home near Wheaton, where Collings raped and killed her. A searcher found her body a week after her disappearance in a sinkhole in McDonald County.

Rowan's stepfather, David Spears, was charged with murder and rape along with Collings. Spears pleaded guilty to reduced charges of child endangerment and hindering prosecution. Prosecutors said there was no physical evidence tying Spears to the killing.

"I keep her (Rowan's) picture on the wall above my desk," Copeland said. "It's a case we won't forget."