The Indiana Supreme Court has denied requests from the attorneys of Joseph E. Corcoran to stop his execution, which is scheduled to be carried out Dec. 18.

Corcoran’s attorneys asked the state’s highest court to halt the execution — which would be the first of a state prisoner since 2009 — arguing his lifelong struggles with mental health problems, including paranoid schizophrenia, have rendered him incapable of understanding the reality of his situation and the punishment he is about to face.

Joanna Green, an Indiana State deputy public defender and one of Corcoran’s attorneys, said the decision handed down Thursday is disappointing and shows that “Indiana endorses executing the insane and the seriously mentally ill.”

“Without a hearing or further examination, the court seemingly determined our client is competent to be executed,” Green said. “The court has not afforded Mr. Corcoran even a modicum of due process. The evidence as presented to the court shows Mr. Corcoran is not competent.”

Corcoran’s attorneys have pointed to his delusions that Indiana Department of Correction officers are torturing him and controlling his mind using an ultrasound machine.

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“Mr. Corcoran’s paranoid schizophrenia completely removes him from reality,” his attorneys argued in motions asking the Supreme Court to stop the execution. “He cannot distinguish between reality and his delusions and hallucinations — his delusions are his reality. And because his reality is informed by his delusions and hallucinations, he is incapable of rational thought.”

Two days before the Supreme Court’s decision, it received an affidavit from Corcoran in which he asked the court to deny his own attorneys’ motions and expressed his wish to be put to death.

“I, Joseph Edward Corcoran, do not wish to litigate my case further. I am guilty of the crime I was convicted of, and accept the findings of all the appellate courts,” Corcoran wrote. “The long drawn out appeal history has addressed all the issues I wished to appeal, such as the issue of competency.”

Green acknowledged her client’s expressed desire for execution. But she said these statements reflect Corcoran’s history of masking his mental illness and his belief that death would allow him to escape a lifetime in prison and the torture he believes was being inflicted upon him.

The Indiana Attorney General’s Office declined to comment.

In court filings, the agency acknowledged that Corcoran is mentally ill — but that he is competent to be executed. Deputy Attorney General Tyler Banks pointed to Corcoran’s own statements saying his claims of being tortured were made up.

Banks argued in court filings that Corcoran’s attorneys’ case for incompetence was based “on a factual premise that Corcoran admits is a lie.”

In 2005, Corcoran wrote an affidavit saying he lied to his psychiatrists in order to get sleep medication, and “no mental illness or delusions or hallucinations” are influencing his decision.

“The truth is no mental illness or delusions or hallucinations are influencing my decision to waive my appeals,” Corcoran wrote. “The fact is I am guilty of murder and I think that I should therefore be executed.”

Corcoran, of Allen County, was convicted and sentenced to death in 1999 for shooting and killing four people, including his own brother. Court documents say he became enraged when he heard the four talking about him. After putting his 7-year-old niece in an upstairs bedroom, Corcoran loaded his semiautomatic rifle and shot the victims. He then put his rifle down, went to the neighbor’s house and asked them to call the police.

Indiana has not executed an inmate since 2009. The state paused executions because of a lawsuit and other complications that prevented officials from obtaining the mixture of drugs used in its lethal injection protocol. In June, Gov. Eric Holcomb and Attorney General Todd Rokita announced they are seeking to resume executions after prison officials acquired the drug pentobarbital to carry out death sentences.

Seven other people are on Indiana’s death row.

Contact IndyStar reporter Kristine Phillips at (317) 444-3026 or at kphillips@indystar.com.