It was merely the latest move by the government aimed at undermining democratic norms.

Will voters condone it? We’re about to see. Next month’s elections will essentially be a plebiscite on the rule of Jaroslaw Kaczynski, the strong and unchallenged leader of the ruling party. Supported by his parliamentary majority and a subservient president, Kaczynski has so far governed according to the classic authoritarian script. In their book “How Democracies Die,” Harvard political scientists Steven Levitsky and Daniel Ziblatt show how elected authoritarians employ three strategies to entrench their power. They capture the referees, sideline rival players and rewrite the rules. Law and Justice has done all these things — though Kaczynski has not yet taken them as far as Viktor Orban, his friend and role model in Hungary.

First, Law and Justice captured the referees. It paralyzed the powerful Constitutional Tribunal, and it subordinated the judges to the will of the government.

Second, the party has marginalized rival players. It has used its parliamentary power to restrict the opposition’s role in making laws. It has state media to ridicule and demonize members of the opposition. It has used defamation laws to silence its critics.

Third, it has rewritten the rules of the political game by altering the meaning of the constitution. Most ominously, the government has diluted electoral laws by packing the offices of electoral commissioners with loyalists. Laws directly relevant to the political process have been amended to be more government-friendly, not least by giving preference to pro-government and church-sponsored public assemblies.

But none of these mutilations of constitutional democracy has been pushed to the limit. Poland still has significant democratic assets, including many judges, the independent nonstate media and a vibrant civil society. In the lead-up to this election, Law and Justice has not disguised its plans. The government has realized that a rule-of-law agenda is not a high priority for a large proportion of the electorate. And through various statements of ruling party leaders, Law and Justice has revealed its blueprint for its second consecutive term of office.

Some changes will be easy. The terms of office of Supreme Court Chief Justice Malgorzata Gersdorf and Polish ombudsman Adam Bodnar will expire in 2020. When these two courageous defenders of the rule of law step down, Kaczynski’s government will find it easy to replace them with obedient lawyers. Ditto for the five vacancies on the Constitutional Tribunal, whose membership still includes a minority of judges appointed by democratic parties before 2015.

Other probable changes are even more worrying. Law and Justice abhors the existence of a free and critical media. The government has already revealed that it intends to ensure a more amenable climate by changing rules on foreign ownership. Currently, several independent media outlets have significant foreign investors, and transferring them to Polish owners will effectively mean subordinating them to the government.

Since the mayors of Poland’s big cities, including Warsaw, all oppose Law and Justice, the party aims to limit the powers and resources of local government. The government is also planning to impose strict rules — not unlike those in Russia or Hungary — on private organizations. And it will launch its main assault on the remaining recalcitrant judges. The ruling party appears to be preparing a new court statute that will allow it to sack any judges and replace them with more accommodating ones.

Opinion polls show Law and Justice and the combined opposition parties in a dead heat. There is just more than 40 percent support on both sides, with a marginal surplus for the opposition. Yet the electoral system of converting raw votes into parliamentary seats favors the ruling party — especially if many votes are cast for micro-parties that don’t make it into parliament because they miss the constitutional threshold of 5 percent. These “wasted votes” (which are estimate to make up about 8 percent of the total) will effectively benefit Kaczynski’s party.

Whatever the outcome, it will reverberate throughout Europe. If the democratic opposition wins, it will show that the progress of dangerous, xenophobic populism throughout Europe can be stopped. If Law and Justice is reelected, however, populists around the continent can rightly count that as a huge boost for their cause, since Central Europe’s largest post-communist state will be poised to entrench illiberal institutions and practices for a long time to come. That could include moving Poland away from the European Union, which has earned the ruling party’s ire by insisting that it stick to democratic standards.

No less than the continued existence of Polish democracy is at stake.