A Seoul court on Thursday acquitted a former head of the Seoul police agency of hampering a police investigation into allegations that the nation's intelligence agency meddled in the 2012 presidential election.

The Seoul Central District Court delivered a not-guilty verdict to Kim Yong-pan, the former chief of the Seoul Metropolitan Police Agency (SMPA), citing a lack of evidence and credibility of a key witness testimony.

Kim was indicted on charges of abusing his authority to cover up the case by deliberately hiding key evidence alleging that the National Intelligence Service (NIS) systematically intervened in the presidential election, in breach of the Police Officers Act.

The 56-year-old former SMPA chief was further charged with violating the Public Official Election Act by allegedly ordering his subordinates to reduce the scale of the scandal and announcing a downsized outcome of the investigation into the election scandal.

Prosecutors initially asked the court to sentence Kim to four years behind bars for violating the two laws.

"There is not enough evidence to acknowledge that the defendant attempted to cover up the case and suspicions surrounding the NIS,"

Judge Lee Buhn-gyun said in his ruling.

Charges against Kim were brought to attention after Kwon Eun-hee, a lead investigator on the case at the time, claimed that she could not fully look into the case due to immense pressure from her superiors, including Kim.

"The testimony of Kwon, the former senior investigator at the Suseo Police Station, lacks credibility when it is the only indirect evidence presented by the prosecution," the judge said, adding that other witnesses had provided contradicting testimony during trials.

The verdict is likely to influence other court cases related to the election-meddling scandal, according to legal experts.

Won Sei-hoon, the former NIS chief, is currently standing trial on charges of ordering some of his agents to use the Internet to sway public opinion in favor of President Park Geun-hye, the then ruling party candidate, ahead of the presidential vote.

The court is scheduled to deliver a verdict for Won later this month, court officials said. (Yonhap)