(CNN) A Ku Klux Klan group's legal battle to pick up highway trash continues after Georgia's highest court unanimously ruled in the group's favor Tuesday.

The Georgia Supreme Court dismissed an appeal by the Georgia Department of Transportation. A lower court had ruled the agency violated the Klan group's free speech rights when it denied its application to participate in an "Adopt-A-Highway" program.

The state suspended the highway cleanup program in 2012, shortly after the controversy broke out.

The case raised important questions about the state's right to claim immunity and the constitutional guarantee of free speech, Justice Keith Blackwell wrote for the court.

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Ultimately, however, the decision rested on jurisdiction, Blackwell wrote. The transportation department filed its appeal incorrectly, leaving the court without the authority to consider its claims.

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