He also urged the Supreme Court to forward every substantiated election complaint to prosecutors so that potential irregularities could be properly investigated.
Tusk made the comments amid an unprecedented wave of legal challenges following the presidential vote, prompting a court-ordered review of ballots from 13 polling stations.
While ruling out any blanket attempt to invalidate the vote, Tusk said on Friday that the legitimacy of the outcome depends on resolving every serious challenge, regardless of how many polling stations might be involved.
"These elections won't be valid in the eyes of the public unless we clarify these concerns," he said.
He cited specific irregularities in the southern city of Bielsko-Biała, where ballots cast for centrist Warsaw Mayor Rafał Trzaskowski were either misattributed or bundled with those for conservative Karol Nawrocki, who narrowly emerged the winner in a blow to Tusk's ruling pro-European coalition government.
According to Tusk, preliminary analysis suggests unexpected voting patterns in around 800 polling stations.
"Statistics clearly show something is off," he told reporters, adding that inconsistencies uncovered so far may stem from mistakes, manipulation or fraud.
The prime minister stressed that while the government cannot interfere with the courts, prosecutors can and must act if there is suspicion of criminal wrongdoing, state news agency PAP reported.
"It is not their job to dispute the election result, but to investigate where there are signs of falsification or misconduct," he said, noting that about 150–160 formal challenges had already been passed on by the Supreme Court.
Tusk also reiterated that, under Poland’s constitution, citizens have the right to challenge election outcomes, and all protests must be examined thoroughly and respectfully.
"We cannot assume elections are valid or invalid in advance; we need to investigate first," he said.
In a follow-up post on the X social media platform, he wrote: "Every protest must be checked. Every case of doubt must trigger a recount. Period."
A further point of contention is which judicial body has the authority to validate the election result.
Under current law, that responsibility lies with the Supreme Court’s Chamber of Extraordinary Review and Public Affairs, a body composed of judges appointed after 2017 via procedures heavily criticised by the EU Court of Justice and the European Court of Human Rights.
The Court of Justice of the European Union has ruled that the chamber "does not have the status of an independent and impartial tribunal."
The government has questioned the legality of this chamber and passed legislation in January assigning election oversight to the 15 most senior Supreme Court judges instead.
But President Andrzej Duda vetoed the bill.
On Friday, Tusk appealed to the outgoing president to reverse that decision, saying: "Withdraw the veto, Mr. President. That would give us judges whose rulings everyone could accept."
Unless the veto is withdrawn, the disputed chamber is legally obliged to decide on the validity of the presidential election by July 2—30 days after the official results were announced.
Supreme Court spokesman Aleksander Stępkowski said on Friday that while no hearing date has yet been set, the chamber intends to meet the deadline, even though it may be forced to process over 50,000 protests.
"That’s a massive undertaking," he said.
(rt/gs)
Source: IAR, PAP