"Its leaders say the measure - which among other things, ousts the current Supreme Court judges - is aimed at reforming the judicial system and to ensure any vestiges of communism are purged".
Poland's lawmakers on Thursday approved a law that gives the president, not judges, the power to regulate the work of the Supreme Court and to appoint its judges.
Jaroslaw Kaczynski, head of Poland's ruling Law and Justice party, contends the judiciary still works along a communist-era model and harbors many judges from that time.
The crowd later moved to the parliament building where a Senate commission was debating the Supreme Court law, ahead of Senate's Friday session.
Even before the Senate voted on the measure, Duda posted a tweet announcing that he'll meet with the president of the Supreme Court, Malgorzata Gersdorf, on Monday at 11 a.m.
Szydlo insisted the government will not bow to pressure "from Polish or from foreign defenders of the interest of the elites".
The opposition says the changes are unconstitutional and destroy judicial independence.
An opinion poll for private television TVN showed on Friday that 55 percent of respondents said President Andrzej Duda should veto the overhaul of the judiciary, 29 percent said he should not veto it. Duda has so far followed the ruling party line.More news: The conditions for OJ Simpson's release from prison have been revealed
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The Polish government has continued to pursue legislation that appears to undermine judicial independence and weaken the rule of law in Poland. The bill was not subject to any public consultation and was passed by the lower chamber just nine days after it was first submitted.
Since coming into power in 2015, the PiS has sought to tighten government influence over courts, and brought prosecutors and state media under direct government control.
The new law would allow Duda to choose who gets to stay on the court and to name new judges to replace anyone he wants to remove.
In Trump's troubling and unusual speech in Poland two weeks ago, the USA president said he was honored "to address the Polish nation that so many generations have dreamed of: a Poland that is safe, strong, and free".
It is unlikely that the European Union would be able to remove Poland's voting rights over its judicial reforms, for instance, because Hungary would be able to veto such a motion and has indicated its willingness to do so. He says the justice system needs "radical changes" to become efficient and reliable.
The Supreme Court bill, which has drawn condemnation from the European Union and has led to street protests, is expected to pass Thursday as the parliament is dominated by the ruling Law and Justice party.
Public protests are planned for Thursday evening.
The U.S. Department of State on Friday urged all sides to "ensure that any judicial reform does not violate Poland's constitution or global legal obligations and respects the principles of judicial independence and separation of powers", and urged dialogue.