A state appeals court Friday tossed out the aggravated battery conviction that could have sent a black teenager to prison for 15 years in last year's beating of a white classmate in the racially tense north Louisiana town of Jena.

Mychal Bell, who was 16 at the time of the December beating, should not have been tried as an adult on the battery charge, the state Third Circuit Court of Appeal in Lake Charles ruled late Friday.

Bell is one of six black Jena High School students charged in an attack on fellow student Justin Barker, and one of five originally charged as adults with attempted second-degree murder.

The charges brought widespread criticism that blacks were being treated more harshly than whites after racial altercations at their school.

He was to be sentenced this coming Thursday in a case that has brought international attention to Jena. Civil rights leaders, including the Revs. Jesse Jackson and Al Sharpton, have been planning a rally in support of the teens that same day.

While teenagers can be tried as adults in Louisiana for some violent crimes, including attempted murder, aggravated battery is not one of those crimes. Defense lawyers had argued that the aggravated battery case should not have been tried in adult court once the attempted murder charge was reduced.

"The defendant was not tried on an offense which could have subjected him to the jurisdiction of the criminal court," the three-paragraph ruling said.

The case "remains exclusively in juvenile court," the Third Circuit ruled.