Mark Christeson, 37, was executed at the state prison in Bonne Terre, Missouri, Tuesday night. It was the first execution in the state since May 2016.

According to the St. Louis Post-Dispatch, as the lethal injection was administered, Christeson appeared to mouth “I love you” a few times to people who were gathered to watch the execution, and his eyes soon closed. He was pronounced dead at 7:05 p.m. local time, eight minutes after the lethal injection began, a Department of Corrections spokesman said.

The US Supreme Court refused to grant Christeson a stay of execution. Newly elected Missouri Governor Eric Greitens, a Republican, also refused clemency. In a statement Tuesday, the Republican said he “thoughtfully considered the facts” of Christeson’s case and chose not intervene.

Christeson was convicted and sentenced to death for the brutal murders of a mother and her two children in southern Missouri. Christeson, then 18, and his cousin Jesse Carter, 17, raped Susan Brouk and then murdered her and her daughter Adrian, 12, and son Kyle, 9.

Christeson was the first person executed in the state since 1989 to have had no federal appeals review, an unconstitutional violation of due process, after his previous attorneys missed a key filing deadline for court papers in 2005. Once the missed filing came to light, the attorneys also refused to cooperate and kept the information from their developmentally disabled client.

For years afterward, Christeson’s lawyers also prevented him from seeking new counsel, and courts eventually declared that all of his claims for relief had now been waived and he was “procedurally barred” from review. These issues led the US Supreme Court to intervene in 2014, granting a stay only hours before his appointed execution.

The Court sent the case back to the lower courts, which were directed to appoint new, conflict-free counsel for Christeson.

While the federal trial court appointed a new attorney to represent Christeson, it approved only 6 percent of the requested budget for the counsel. This created a new conflict of interest for substitute counsel, who did not have the funding to investigate and assess his severe intellectual impairment.

Attorneys appointed to challenge Christeson’s 2014 scheduled execution carried out an initial review of his records, which found that his mental impairment was likely due to some combination of chemical exposure in utero, several concussions leading to unconsciousness, and sexual and physical abuse from infancy through childhood.

The attorneys also uncovered records showing he had failed in special education classes and scored only 74 on an IQ test. This history has never been even cursorily reviewed by the courts, and Christeson was never subject to a comprehensive social evaluation with psychological testing.

In January 2015, the Supreme Court threw out a ruling by the Eighth Circuit Court of Appeals denying Christeson another chance to have his case heard. But before the appeals court had decided whether to consider Christeson’s appeal of its ruling that he was “procedurally barred” from review, the state of Missouri proceeded to set his execution date for January 31.

Governor Greitens, who denied clemency under these conditions, recently noted, “As a constitutional conservative, I believe, as you do, that the Constitution applies to every citizen. I believe in the Sixth Amendment, which guarantees the right to a fair trial and adequate legal representation for all.”

Greitens, a former Navy SEAL, spent the weekend in the nation’s capital meeting with Vice President Mike Pence. He has made no comment on President Donald Trump’s executive order banning travel for residents of seven predominantly Muslim countries.

About 200 people have been sentenced to death in Missouri since the state reenacted the death penalty in 1975. Eighty-seven people have been put to death.

There are currently 25 men on death row in the state, according to the Death Penalty Information Center, including two who have been declared mentally unfit for execution and two who were granted stays due to medical conditions that might make their executions painful.