A Seoul court on Monday acquitted 45 people on charges of proxy voting in selecting a minor opposition party's proportional candidates ahead of last year's April parliamentary elections.

With similar cases pending in the court, legal experts expect the ruling could affect the verdicts of some 400 other people who are standing trials in connection with the Unified Progressive Party (UPP) election fraud scandal.

The scandal centers around allegations that votes were cast en masse through a single Internet Protocol (IP) address in the UPP's primary for proportional representation seats that took place in March 2012.

IP addresses, the online equivalent of a street address or a phone number, should be different for each voter. Multiple or proxy voting allegedly happened with offline ballots as well.

The 45 people, including the party's key member Cho Yang-won, were indicted on charges of proxy voting through mobile phones using IP addresses of their family members or friends.

The Seoul Central District Court delivered not-guilty verdicts, saying that the law does not stipulate that a direct election must be carried out in the party's primary.

After the allegations were raised, four UPP co-leaders resigned over the vote-rigging scandal. The party also recently suffered an internal feud after its key members and Rep. Lee Seok-ki were indicted on charges of plotting to overthrow the government. (Yonhap News)