Grzegorz Schetyna, leader of Poland's largest opposition party, the Civic Platform (PO), which organised the march, kicked off the event saying that it would lead to “freedom, to an election win”.
Schetyna referred to a statement by the leader of the PiS party, Jarosław Kaczyński, who said there was no threat to the country's freedom.
Speaking ahead of the march, Kaczyński said “only a total failure to see reality could lead someone to the conclusion that there is a threat to freedom” in Poland.
“We have a democracy, everyone can have their opinion, everyone can protest, everyone can vote as they please, everyone can write what they want, we completely guarantee it,” Kaczyński said.
“This is not true and we know it,” said Schetyna at the start of the march.
He also mentioned looming changes to education and called for a referendum on stopping the government's plan to do away with middle schools. The changes are set to come into force in September.
Other officials from the PO party said the march was in defence of local government and the judiciary, criticising the government's initiatives in these sectors.
After coming to power in October 2015, PiS introduced changes to the constitutional tribunal which drew criticism domestically and abroad and led to a European Commission inquiry into the rule of law in Poland.
PiS has argued it was unfair that a constitutional court with a majority of judges appointed by the previous parliament should be able to scupper flagship policies for which Law and Justice secured a mandate in democratic elections in late 2015.
PiS also said that it responded to the EC's concerns.
The government has also suggested changes to the way judges are appointed to certain positions, having called the courts out for taking too long to hear cases, while PiS supporters have accused judges of being an elite, self-serving clique often out of touch with the problems of ordinary citizens
But “judges must be independent,” said PO MP and former justice minister Borys Budka.
The government has also suggested limiting the time spent in the office of mayor in Poland to two terms.
According to police statistics, some 12,000 people took part in Saturday's march, while City Hall put the figure at 90,000.
Besides PO officials, high-ranking members of other opposition parties, the leader of the Polish Teachers' Union, a former Constitutional Tribunal judge and celebrities took part in the march. (vb/pk)
Source: PAP, IAR