But Paweł Mucha, a presidential aide, said Gersdorf was "going into retirement in accordance with the law", which took effect at midnight on Tuesday, and insisted the supreme court was now "headed by Judge Józef Iwulski", who was chosen by the president.
Insisting that "the constitution gives me a six-year term", Gersdorf, who is 65, has refused to comply with the reforms that require her to step down immediately, cutting short her tenure slated to end in 2020.
"My presence here is not about politics, I am here to protect the rule of law", Gersdorf, who is 65, said at the court's entrance, surrounded by supporters and opposition politicians.
She believes that recent legislation pushed through by the ruling Law and Justice party (PiS) to force more than a third of Supreme Court judges to retire is unconstitutional.
Poland's Prime Minister Mateusz Morawiecki, left, is welcomed by European Commission President Jean-Claude Juncker in Brussels on March 8.
Critics say that the Polish government is eroding the rule of law and that its so-called reforms are meant to give it control of the judiciary.
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Labor Department for additional visas for foreign servers and cooks, according to records submitted Thursday and Friday . This year, the pay for a cook at Mar-a-Lago starts at $13.31 per hour - down three cents from the year before.
The 26 other justices also showed up for work Wednesday.
Hailing from a renowned Warsaw family with deep roots in the legal profession, Gersdorf's father Miroslaw was also a respected law professor and judge.
"What if I have a court case against someone from PiS and they will be able to influence judges".
"We are calling for the reform to be amended in line with the constitution and European standards".
Mucha also announced that Jozef Iwulski, now the longest-serving Supreme Court judge, will take over Gersdorf's duties as acting 1st President of the court from Wednesday.
Chanting "We are with you!", some 5,000 protesters rallied on Tuesday evening at the Supreme Court's offices in central Warsaw in support of Gersdorf and other judges.
Hundreds protest outside the Supreme Court building in Warsaw on Wednesday.
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LAPD SWAT officers went into the home and discovered the unidentified man's body early Saturday morning after shots were fired. While no officers were hurt, at least one of them discharged a weapon, according to the Police Department.
A supreme court spokesman confirmed Gersdorf had been invited and would attend the afternoon meeting with Duda, but said he did not know what the objective of the meeting was. "The court system.is an entirely internal matter", PiS leader Jaroslaw Kaczynski was quoted by the PAP news agency on Tuesday as telling Gazeta Polska newspaper.
On the eve of the changes, Supreme Court spokesman, judge Michal Laskowski, said it was not yet clear if the president would use his power to immediately force the retirement of the judges, including the court president Malgorzata Gersdorf.
Poland's government says the new rules are necessary and will help strengthen democracy.
Warsaw faces the threat of losing its voting rights in the bloc under a procedure launched late a year ago over judiciary reforms.
Amnesty International last month warned that Polish citizens' human rights were at risk from "systematic erosion of guarantees for an independent judiciary" and urged the Polish government and parliament to amend the laws in question.
The law has drawn condemnation from the European Union, which has opened sanctioning procedures that could potentially strip Poland of its EU voting rights.
Government critics now are putting their hopes in the European Union to preserve the rule of law in their homeland - a message that was reflected in the chants and slogans at the protest.
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The Games of Thrones stars recently got together in Belfast for a goodbye celebration as shooting of the epic series came to the end.