BUDAPEST — The illiberal government in Warsaw is about to deliver a huge blow to Poland’s constitutional system.

Since winning a slim parliamentary majority in 2015, the Law and Justice (PiS) party has been relentless in its attacks on any institution that could oppose it.

In stunning defiance of the Venice Commission — the Council of Europe’s constitutional watchdog — and a host of other European institutions, PiS has methodically taken over the Constitutional Tribunal, the public prosecution authority, and the public broadcasters.

The one check on its consolidation of power has been the Polish judiciary. Now, in a series of dramatic moves, brazen in their contempt for basic European values, PiS is moving to place the judiciary under its control.

On Wednesday, the Polish parliament passed an amendment to a new law on the National Council of Judiciary — a constitutional body tasked with appointing and promoting judges. It was an outrageous move, giving the PiS majority the unconstrained power to elect 22 out of 25 members of the Council.

PiS leader Jarosław Kaczyński appears to be determined to consolidate his authoritarian reign even faster than his fellow strongmen.

But the ruling party was just beginning. Just hours after passing the law on the judiciary council, PiS introduced a new, far more radical bill; if enacted, it will allow the party to complete a nearly full takeover of Poland’s judicial apparatus in a matter of weeks.

The bill provides for the wholesale, on-the-spot dismissal of the entire cadre of 83 top judges currently sitting on Poland’s highest appellate panels. The purge will take place just a day after the law’s promulgation.

The exceptions from this mandatory “retirement” — applicable regardless of judge’s age — will be made in an entirely arbitrary fashion by the PiS-appointed minister of justice. The minister’s decisions will not be subject to any review. All seats thus emptied will be swiftly filled by the new, politically reliable Council of Judiciary.

The new Supreme Court will not only have the final appeal powers over all criminal and civil cases; its autonomous “Disciplinary Chamber” will make final determinations on disciplinary actions against all judges in the country. Disciplinary proceedings will be instituted whenever the minister of justice demands.

When trying to make sense of the increasingly authoritarian laws passed by PiS, many Western commentators tend to compare the situation in Warsaw with that in other “illiberal” regimes in the region. Poland has been run by an authoritarian party for less than two years. Is it not reasonable to assume that the country’s future may resemble that of Hungary (now in Year 7 since the illiberal takeover), Turkey (Year 14) or Russia (Year 18)?

The remarkable escalation that the Supreme Court bill represents suggests that even this outlook may still be overly optimistic. PiS leader Jarosław Kaczyński appears to be determined to consolidate his authoritarian reign even faster than his fellow strongmen.

There are good reasons why. In Hungary, Turkey, and Russia, the authoritarians enjoy convincing, and sometimes overwhelming, social support. In Hungary, for instance, anti-Western parties won more than 65 percent of votes in both the 2010 and the 2014 parliamentary ballots.

Poland, however, is different. In 2015, PiS won a razor-thin majority, only 37.5 percent of the popular vote, the weakest parliamentary victory since 1997 (with the exception of PiS’s own previous, even more fleeting win in 2005). Even if one adds in the support for all illiberal and right-leaning “protest” parties, the total barely exceeds 50 percent.

Since the election, a string of domestic and foreign missteps have further weakened PiS’ support. After the government’s disastrous effort to unseat Poland’s former liberal Prime Minister Donald Tusk as president of the European Council, the two opposition liberal parties briefly overtook PiS in the opinion polls. Indeed, the liberals have polled ahead of PiS for seven out of the last 18 months.

If PiS demonstrates its determination in harassing the opposition, many liberals may be dissuaded from vigorously competing in the next general election.

The Supreme Court bill indicates strongly that Kaczyński may intend to compensate for his electoral weakness by intimidating the opposition with the help of the pliant law enforcement and judicial apparatus.

Poland is a year from local elections — the first important test for the ruling party. Already, suspicious criminal or disciplinary charges have been brought or revived by politically controlled prosecutors against opposition mayors of Lublin, Łódź, Gdańsk, Sopot, and Nowa Sól.

So far, however, the effects of those actions have been mitigated by the highly independent judiciary. With the new, entirely controllable Supreme Court, politically uncooperative judges may find themselves subjected to disciplinary procedures.

If PiS demonstrates its determination in harassing the opposition, many liberals may be dissuaded from vigorously competing in the next general election, scheduled for fall 2019. Any remaining dissent may then be cracked down on with the law enforcement system, which by then will be fully controlled by PiS.

And if, improbably, the opposition still manages to win, the Supreme Court can simply declare the election invalid — which is one of the court’s constitutional competences.

Commentators often ask, what will Europe do about Poland’s swift slide into autocracy? An even more pertinent set of questions concerns the rank-and-file PiS politicians, many of whom distinguished themselves fighting oppression under communism.

Do they really want to be part of a government backed by docile judges as opposed to genuine democratic legitimacy? If not, they should finally stand up to their irresponsible leaders, who are driving the divided country to the authoritarian point of no return.

Maciej Kisilowski is an associate professor of law and public management at Central European University.