As Poland's ruling party moves to take control of the country's high court, protesters are taking to the streets and European Union officials are warning of the possibility of sanctions.There is fear, both within and outside of Poland, that a proposed measure would upend an already-weakened system of checks and balances.The Law and Justice party is conservative, populist, Euro-skeptic and nationalist. Under the leadership of Jaroslaw Kaczynski, who does not hold elective office, the party has already sharply curtailed the power of the judicial branch. In late 2015, shortly after taking power, it passed a law to make it far harder for the Constitutional Tribunal to reject laws as unconstitutional. (The tribunal ruled the change was unconstitutional ... but the government, citing the new law, overruled the judges).Now, the ruling party is targeting the country's highest court of appeals."The proposed bill calls for the immediate dismissal of the current Supreme Court judges, except those chosen by the justice minister," The Associated Press explains. "It would give the justice minister the power to appoint the key court's judges."As part of the proposed overhaul, the legislature has already advanced measures that would give the ruling party more control over lower courts.Kaczynski says the "reforms" are necessary in the name of efficiency. He also accused the courts of being "controlled by lefties" and "foreign forces," The Guardian reports.An EU official, European Commission vice president Frans Timmermans of the Netherlands, said the party's efforts, if successful, "would increase the systemic threat to the rule of law in Poland."If Poland moves forward, Timmermans said, the EU might consider triggering a never-used provision to suspend a member country's voting rights.Meanwhile, demonstrators are marching in Warsaw, Krakow and other Polish cities to protest the threat to the court's independence, the Krakow Post reports. The outlet spoke to a number of demonstrators — including one man who said this was his first protest since the communist era ended nearly three decades ago."Justice should be blind," the man, identified only as Robert, said. "But now she is not. Now she has the face of the Minister of Justice," a powerful party official. The protester said he worried Poland could become "like Russia, Belarus, or even North Korea."Politico EU reports that Polish President Andrzej Duda has taken the unusual step, for him, of challenging his party leadership on this issue. Duda, who was picked by party leader Kaczynski to run for office and largely toes the Law and Justice line, has introduced a version of the bill that gives the party less power.The original bill is being bitterly debated in Parliament, where members of the opposition party have proposed 1,300 amendments, The AP reports. And the debate has gotten personal: