The political crisis stemming from the Choi Soon-sil scandal has entered a crucial stage, with a set of important events scheduled for later this week.

First, the National Assembly will launch its own investigation into the scandal Wednesday, by hearing testimonies from officials at relevant government offices like the Ministry of Culture, Sports and Tourism and the Supreme Prosecutor’s Office. Highlights of the parliamentary investigation, which could last up to 60 days, will be hearings in which business tycoons, as well as Choi and other key players in the scandal, will testify.

Then an independent counsel who will lead a separate investigation is set to be named this week. Opposition parties plan to nominate two candidates Tuesday, of whom President Park Geun-hye should choose one within three days. The counsel will investigate for up to 120 days.

The impeachment process against Park will also start this week. Opposition parties plan to work out their unified impeachment motion by Wednesday, which they said hoped to get through the full session of the parliament either this Friday or next.

We still believe that an orderly relinquishing of power and duties would be better for Park -- and more importantly, for the nation -- than her becoming the first president to be impeached for committing misdeeds while in office.

For instance, Park could set a date in the coming months for her resignation -- a group of former politicians and civic leaders suggested April -- and nominate a new prime minister in consultation with the opposition parties. The prime minister would lead the caretaker government to administer the next presidential election.

That could help parties and candidates -- and voters as well -- better prepare for the presidential poll. This would allow a more orderly transition than a sudden resignation or impeachment, which would give the nation only two months before electing her successor.

All this could be possible only if Park -- instead of digging in -- searched her soul and accepted the popular demand for her to step down from her post. Given how she has reacted to the scandal so far, the chances of that happening are very low.

This is why for now, impeaching Park -- the only possible legal way to punish a sitting president -- should be undertaken resolutely and effectively. What the main opposition Democratic Party of Korea has been doing gives big cause for concern in this regard.

The party -- particularly its leader Choo Mi-ae and leading presidential hopeful Moon Jae-in -- has already been criticized for zig-zagging on the issue and short-sightedness in their dealings with the crisis that has engulfed the nation for more than a month.

Choo once made a unilateral proposal to hold a one-on-one meeting with Park, only to cancel it in the face of opposition from her own party. She has continued to make slips of the tongue to the degree that many see her as unqualified to lead the main opposition party at a crucial time like this.

Choo’s recent comments on the plan to impeach Park show she is wrongheaded and hard-shelled as well. Speaking of a possible alliance with members of the ruling party who support Park’s impeachment, Choo said her party “won’t beg” for votes from them.

This narrow-mindedness contrasts with the People’s Party, whose interim leader Park Jie-won emphasized the need to forge an anti-Park front between the three opposition parties and ruling party members who sympathize with their cause.

After all, the three opposition parties, including the Justice Party, and independents who are close to the opposition side control only 172 parliamentary seats, 28 short of the 200 required to impeach the president.

Moreover, impeaching Park would entail a lot more work at the parliamentary level, which would certainly require the opposition party to cooperate with the Saenuri Party as well as other parties.

The Democratic Party’s arrogant, self-righteous attitude may reflect the liberal party’s sentiment that, with the Choi scandal having alienated voters from the conservative ruling party, it is within reach of power. We have seen many cases in which such unearned political fortunes vanish in the long run.