A man has been executed for brutally killing his daughter despite lawyers arguing he is unaware he was going to be put to death.
Benjamin Cole waited on death row for 20 years after being convicted of murder in 2002.
His lawyers filed a last minute suit in the US District Court for the Northern District of Oklahoma in the hope of the court ordering a competency hearing.
However, the warden of Oklahoma State Penitentiary allegedly refused to initiate the hearing and instead ordered an evaluation by a state doctor in which he was found fully cooperative.
Cole was put to death via lethal injection shortly at 10.22am local time (4.22pm BST) in the Oklahoma State Penitentiary, Oklahoma, US, executed for a crime that shocked the nation.
He had been playing video games when he was interrupted by the cries of his nine-month old daughter Brianna Victoria Cole.
In anger he grabbed his daughter's ankles as she lay on her stomach and forced them up to her head, breaking her spine and causing her to bleed to death.
He then returned to his video game.
The case went to trial, and lawyer Emma Rolls said Cole did not plead guilty due to his mental condition.
They argued he was suffering from schizophrenia, caused by an identified brain lesion and other factors, for example the extreme abuse he received as a child.
"He had some fixed delusions on very hyper-religious ideology and he was offered a deal after he gave full confession accepting responsibility for the death of his daughter," Rolls said. "I believe that if he were competent he would have taken that deal to save his life, but he rejected it.
"I think that speaks to how mentally ill he was even before this trial started."
According to the Oklahoma Department of Corrections for his last meal Cole had vegetarian lasagna, salad with dressing, tortilla and a fruit drink packet.
He didn’t request anything special so was given the facility religious meal. He ate it at 7.30pm Wednesday and had no food on the day of execution.
A last minute application for a stay of the execution, filed the night before his execution, was denied by the Supreme Court.
A statement from Tom Hird, one of Cole's lawyers, in the wake of the execution, read: “Benjamin Cole was a person with serious mental illness whose schizophrenia and brain damage went undiagnosed and untreated for many years, eventually leading to the tragic crime for which he was executed.
"Over his years on death row, Ben slipped into a world of delusion and darkness. Although I represented him for many years, he was often unable to interact with my colleagues and me in any meaningful way. As Ben’s physical health deteriorated along with his mind, he became progressively more detached from reality, refusing to leave his cell, moving little and with difficulty, and rarely speaking to anyone.
“It is unconscionable that the State denied Ben a competency trial. Ben lacked a rational understanding of why Oklahoma took his life today. As Oklahoma proceeds with its relentless march to execute one mentally ill, traumatized man after another, we should pause to ask whether this is really who we are, and who we want to be.”
Earlier this week, Cole's team also applied for a stay of execution, but it was denied after the court argued that he is mentally fit.
On October 4, Judge Mike Hogan disagreed with the arguments of Cole's lawyers for a competency trial, despite expert reports on the prisoner's mental state being "conflicting".
"The state courts’ acknowledgement that experts reached conflicting opinions about Ben Cole’s competency should have been all they needed to order a full competency hearing," attorney Rolls said.
Cole was the 202nd person to be executed in Oklahoma since 1915. The state has the highest number of executions per capita in the US.
