TAIPEI (Taiwan News) — The Shilin District Court in Taipei City declared itself unauthorized to rule Wednesday (Jan. 26) in the case of the manufacturing of an illegal firearm in the United States by Taiwan student An Tso “Edward” Sun (孫安佐) four years ago.

The student, the son of celebrities Di Ying (狄鶯) and Sun Peng (孫鵬), was nabbed in March 2018 after a fellow student reported a threat he made of planning a mass shooting at his school in Pennsylvania. He served eight months in detention before being allowed to return to Taiwan.

An attorney for Sun welcomed Wednesday’s court decision, though an appeal by prosecutors was still possible, CNA reported. The student had initially claimed his threat was a joke, but a police search of his home had turned up 1,600 rounds of ammunition and separate gun parts bought online.

The district court said that because of differences between Taiwan and U.S. legislation on the subject of attempting to manufacture a gun, it was unable to pronounce a verdict on the issue. Buying parts for a gun and failing to succeed in assembling them was reportedly not an offense in the U.S., the court said, even though it was covered by Taiwan’s Controlling Guns, Ammunition and Knives Act.