Corey Johnson, who is set to be executed by the federal government on January 14, filed Friday for a stay of execution with the US Fourth Circuit Court of Appeals. His lawyers argue that his upcoming execution is unconstitutional because significant evidence of his intellectual disability was not considered at trial.

In 1993, Johnson was convicted of several gang-related murders. His defense team at the time claimed that he was not intellectually disabled, relying on flawed evidence from unreliable IQ tests. His lawyers say this decision was reached “without the current understanding in the medical and legal community of what constitutes an intellectual disability and without an accurate or complete picture of his intellectual functioning, based on, among other evidence, valid, properly adjusted IQ scores.”

His pending clemency petition details early evidence of his disability. He was in the second grade for three years. He also repeated both the third and fourth grades. He did not know his birthday at age eight and could barely write his name at thirteen. His lawyers claim that these inherent challenges were also exacerbated by abuse, trauma, and instability throughout his childhood.

In 2002, the Supreme Court ruled in Atkins v. Virginia that it was unconstitutional to sentence people with intellectual disabilities to death. This ruling provides a three-step test to determine whether defendants are intellectually disabled, which attorneys and experts say Johnson meets.

But courts have never heard the full scope of evidence uncovered by his current legal team. Johnson’s appeal requests a hearing on the new evidence of his disability. Alfred Bourgeois, who was executed by the federal government in early December, was allowed a similar hearing prior to his execution.

If granted, Johnson’s execution could be postponed until after President-elect Biden takes office. Biden has spoken in favor of abolishing the federal death penalty but has not specified when he would take action.

Lisa Montgomery, the only woman on federal death row, is also set to be executed next week. Her legal team also claims that intellectual disability and childhood trauma were not adequately considered in her sentencing. The Death Penalty Information Center reports that a combination of severe childhood trauma, intellectual disability, and mental illness exemplify the problem with many death penalty cases.