The ruling Saenuri Party has been rocked by allegations that one of its lawmakers bribed her way into parliament. If the suspicion surrounding Rep. Hyun Young-hee proves true, it would deal a serious blow not only to the party but to its leading presidential hopeful Park Geun-hye. Park led the party through the April general elections as interim party chief.

The National Election Commission asked the prosecution last week to investigate allegations that Hyun became a proportional representative candidate after giving money to a member of the party’s nomination committee and a former party chief ahead of the elections.

All those involved in the scandal have vehemently denied the charges but NEC officials say testimonies by the lawmaker’s former driver appear plausible.

If proven true, the case could deal a serious blow to Park’s bid to become the nation’s first female president in the December vote.

Park, then head of Saenuri’s interim emergency council, pledged to select parliamentary candidates based on fair and objective standards as part of efforts to reform the party’s image of indulging in vested interests and paying little attention to the difficult livelihoods of the people.

The 10-member nomination committee formed by Park was supposed to reflect her wish in the selection process. Particularly, the member suspected of receiving 300 million won ($265,000) from Rep. Hyun is known to be close to Park.

The party has been trying to contain the fallout of the scandal by pressuring the two figures in question to leave it voluntarily. The former party chief suspected of receiving 20 million won from Rep. Hyun retired from politics after losing his parliamentary seat in the April elections.

Whether they remain in the party or not, however, would make little difference to the political damage Park would suffer if the allegations are confirmed, angering the voters who gave a majority of parliamentary seats to her party in the elections.

The prosecution should make a thorough and speedy investigation into the case to prevent it from overshadowing the presidential race, which should be focused on candidates’ policies and stances on key issues rather than accusations not backed by hard evidence. It does not appear to take prosecutors long to unearth the truth if they are determined to conduct the investigation without any political consideration. Both Rep. Hyun and the former nomination committee member, Hyun Ki-hwan, have expressed willingness to cooperate with the probe.

A decisive clue may be found by confirming allegations by the lawmaker’s former driver that Hyun Ki-hwan exchanged text messages with a man who allegedly delivered the money to him in March. Hyun has denied the text message exchange.

The scandal has provided ammunition for Park’s rival contenders in the party’s primary presidential race to attack her. They threaten to boycott the race unless the party chairman, Rep. Hwang Woo-yea, who is close to Park, steps down to take responsibility for the scandal. Three of the four competitors with Park refused to join a TV debate on Friday night. Park’s aides criticized them for attempting to derail the nomination race and drag her down from the frontrunner status.

The three presidential runners appear to be overreacting to the scandal, as it may be reasonable to decide on what measures should be taken with regard to it after suspicions are cleared up by the ongoing investigation. It is thought to be a more responsible attitude as presidential hopefuls to run through the nomination contest.

Regardless of the outcome of the probe, the latest scandal should serve to sever the practice of receiving cash in exchange for nominations for elected posts, which have plagued the political circles for the past decades. In a separate case, prosecutors are investigating allegations that officials of a minor opposition party gave a political aspirant a proportional representative ticket in return for his promise to lend 5 billion won to the party ahead of the April elections.

Election and political funding laws should be revised to permanently ban politicians convicted of selling candidacy from running for parliamentary seats or other elected posts. Park and other presidential contenders in both the ruling and opposition parties should announce firm and concrete measures to eradicate the practice before hurling political accusations against each other.