A federal appeals court on Tuesday threw out the conviction of Salim Ahmed Hamdan, a former driver for Osama bin Laden who served a prison term for material support for terrorism.

In a 3-0 ruling, the appeals court said that material support for terrorism was not an international-law war crime at the time Hamdan engaged in the activity for which he was convicted.

Hamdan was sentenced to 5 1/2 years, given credit for time served and is back home in Yemen, reportedly working as a taxi driver.

"If the government wanted to charge Hamdan with aiding and abetting terrorism or some other war crime that was sufficiently rooted in the international law of war at the time of Hamdan's conduct, it should have done so," wrote Judge Brett Kavanaugh of the U.S. Circuit Court of Appeals for the District of Columbia. He was joined by two other judges, all appointed by Republican presidents.

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