The nation's top court has returned to a lower military court a ruling that convicted an army officer of criticizing the ruling party on social media in violation of the Public Servant's Act, court officials said Wednesday.

The captain, whose identity was withheld, was indicted in 2013 over tweeting negative comments about the Saenuri Party during the 2012 presidential election.

The current law prohibits civil servants from taking part in political activities such as holding rallies or voicing political opinions in public.

The High Court for Armed Forces ordered him to pay a fine of 2 million won ($1,700).

The Supreme Court, however, overturned the decision made by the military appeals court, saying part of the tweets prosecutors claimed as criticizing the ruling party were irrelevant to the election or were even written in favor of the party.

The court said comments such as "the ruling and opposition parties are basically the same" or that "(all the channels are broadcasting) live debates while I need to monitor news reports," cannot be deemed as expressing political opinions.

"The appeals court found the whole set of tweets illegal," the court said. "(It should have) examined them more thoroughly based on the specific content and context to determine whether they were against the Saenuri Party. (Yonhap)