A death row inmate in Missouri who has long claimed his innocence and is scheduled to be executed in less than one week asked the US Supreme Court on Wednesday for a stay of execution, arguing his due process rights were denied during the yearslong legal battle to save his life.

The president of the NAACP is urging Missouri's governor to halt the execution of Marcellus Williams scheduled for Tuesday, writing that executing a Black man who says he was wrongfully convicted would amount to a “horrible miscarriage of justice.