Story highlights Stinney was executed for killing two girls some 70 years ago in South Carolina

A judge rules a violation of his due process rights "tainted his prosecution"

She says sentencing a 14-year-old to death constitutes cruel and unusual punishment

(CNN) A judge has vacated the conviction of a 14-year-old boy who was executed for allegedly killing two girls some 70 years ago in South Carolina.

The judgment against George Stinney, the youngest person to be executed by an American state since the 1800s, effectively exonerates the boy, said family attorney Matt Burgess.

A black teen in the Jim Crow South, Stinney was accused of murdering two white girls, ages 7 and 11, as they hunted for wildflowers in Alcolu, about 50 miles southeast of Columbia.

Stinney, according to police, confessed to the crime.

No witness or evidence that might vindicate him was presented during a trial that was over in fewer than three hours. An all-white jury convicted him in a flash, 10 minutes.

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