Appointing judge Julia Przyłębska, the first woman to hold the post, Duda appealed to her to ensure the Constitutional Tribunal works “dynamically” and hears cases without delay.
“First of all I would like the [new] head judge to clear up the Tribunal’s issues. I would like the scandalous disputes both inside and around the Tribunal to end... they have impeded the Tribunal from functioning properly,” Duda said.
The appointment of Przyłębska came two days after the term of the previous Tribunal head, Andrzej Rzepliński, ended.
On Tuesday, Duda appointed Przyłębska to serve as the acting head of the Constitutional Tribunal.
That move was hailed by the conservative niezależna.pl website as marking “the end of the Constitutional Tribunal crisis”.
Przyłębska was nominated by the conservative Law and Justice (PiS) party.
PiS has pushed through sweeping legal and other reforms since winning an outright parliamentary majority last year. EU institutions and politicians have accused it of eroding democracy, charges which PiS denies.
Critics have accused Law and Justice of aiming to stack the Constitutional Tribunal with PiS supporters, undermining its ability to challenge new laws.
Law and Justice has argued it is unfair that a constitutional court with a majority of judges appointed under the previous parliament should be able to scupper flagship policies for which PiS secured a mandate in democratic elections.
Przyłębska’s appointment is controversial. The Vice President of the Constitutional Tribunal, Stanisław Biernat, said that eight Tribunal judges on Tuesday refused to vote on candidates for the post of the court’s new head.
He said that six judges took part in the vote, adding that for the ballot to be valid at least half of the 15-member court should vote.
But judge Mariusz Muszyński told the PAP news agency that Tuesday's choice of candidates was valid.
Kamila Gasiuk-Pihowicz, an MP for the opposition Nowoczesna party, accused the president of “acting against Polish national interests.”
She said: “The constitution is unequivocal. Candidates who can be appointed by the president should have the support of a majority of the judges on the Constitutional Tribunal. This is not this case here.” (pk)