"I think it's a longshot, but I admire the lawyer for trying it," Gaines said, adding that he's not aware of any other executed inmates in the state being granted a new trial posthumously.
The request for a new trial is largely symbolic, but Stinney's supporters say they would prefer exoneration to a pardon.
Stinney's case intersects some long-running disputes in the American legal system — the death penalty and race. At 14, he's the youngest person executed in the United States in past 100 years. He was electrocuted just 84 days after the girls were killed in March 1944.
The request for a new trial includes sworn statements from two of Stinney's siblings who say he was with them the entire day the girls were killed. Notes from Stinney's confession and most other information deputies and prosecutors used to convict Stinney in a one-day trial have disappeared along with any transcript of the proceedings. Only a few pages of cryptic, hand-written notes remain, according to the motion.
"Why was George Stinney electrocuted? The state can't produce any paperwork to justify why he was," said George Frierson, a local school board member who grew up in Stinney's hometown hearing stories about the case and decided six years ago to start studying it and pushing for exoneration.
The South Carolina Attorney General's Office will likely argue the other side of the case before the Clarendon County judge. A spokesman said their lawyers had not seen the motion and do not comment on pending cases. A date for a hearing on the matter has not been set.
The girls were last seen looking for wildflowers in the tiny, racially-divided mill town of Alcolu about 50 miles southeast of Columbia. Stinney's sister, who was 7 at the time, said in her new affidavit that she and her brother were letting their cow graze when the girls asked them where they could find flowers called maypops. The sister, Amie Ruffner, said her brother told them he didn't know and the girls left.
"It was strange to see them in our area, because white people stayed on their side of Alcolu and we knew our place," Ruffner wrote.
The girls never came home and hundreds of people searched for them through the night. They were found the next morning in a water-filled ditch, their heads beaten with a hard object, likely a railroad spike.
Deputies got a tip the girls had been seen talking to Stinney. They came to Stinney's home and took him away. His family wouldn't see the boy again until after his trial. Newspaper accounts suggested a lynch mob was nearly formed to attack the teen in jail.
Stinney's dad worked for the major mill in town and lived in a company house. He was ordered to leave after his son was arrested, said Stinney's brother Charles Stinney, who was 12 when his older brother was arrested. Charles Stinney's statement explains why the family didn't speak to authorities at the time.
"George's conviction and execution was something my family believed could happen to any of us in the family. Therefore, we made a decision for the safety of the family to leave it be," Charles Stinney wrote in his sworn statement.
Charles Stinney said he remembered the events vividly because "for my family, Friday, March 24, 1944, and the events that followed were our personal 9/11."
Both statements were made in 2009. Lawyer Steve McKenzie said he planned to file the request for a new trial then, but heard from a man in Tennessee who claimed his grandfather was with George Stinney the day of the killings. McKenzie thought the information from someone not related to Stinney would be especially powerful, but the person suddenly stopped cooperating after stringing the lawyers along for years.
The request for a new trial points out that at 95 pounds, Stinney likely couldn't have killed the girls and dragged them to the ditch.