A man who told officers about beating, choking and drowning his five-year-old son at his Patten Towers apartment in 2003 on Monday morning pleaded guilty to second-degree murder.
Dedrick Lamont Atkins, who was 26 at the time of the incident, was sentenced to 15 years in prison.
Prosecutor Neal Pinkston said Atkins has remained in custody since the incident, mainly at the Middle Tennessee Mental Health Institute. He said it was only in 2011 that he was ruled competent to stand trial.
Atkins told Criminal Court Judge Don Poole that he has been "hearing voices" since he was a child.
Judge Poole stressed that he should stay on his medicines "so you do not harm yourself or others."
Atkins had been charged with first-degree murder.
He will be given credit for the time he was held in psychiatric facilities.
Atkins was charged in the death of five-year-old Dedric Johnson. The child was found lifeless in his father's third-floor apartment after his father reported him dead to the lobby security guard, who in turn called police and paramedics.
Atkins, who has a lengthy criminal record, was interviewed for several hours afterward at the Police Service Center by both child abuse and homicide detectives.
Police said the child died from extreme blunt and physical trauma.
This was five-year-old Dedric's first visitation with his estranged father, it was stated.
Police said Atkins refused to give a statement to officers, but that he "made spontaneous statements to EMS personnel about killing the child. He gave details how he beat, choked and drowned the victim."
It said an examination of the child showed trauma about the head, ligature marks around the neck, and that his clothes were wet.
In 2004, a $1 million lawsuit was filed in the death of the child brought by Sherry Johnson, mother of the young victim.
It was filed against Moccasin Bend Mental Health Institute, Dr. Doloroso B Yap, Patten Towers LP II, Yarco Company and Walden Security.
The suit says the child was killed "by his mentally ill father." It says the father had been released by Moccasin Bend on Sept. 19, though a few days earlier he was deemed too dangerous to be released.
The complaint was also brought against Patten Towers, claiming inadequate security.