WARSAW, Poland -- Poland's most powerful politician has been spotted reading a book about cats during a session of parliament.

Jaroslaw Kaczynski, leader of the country's ruling party, seemed fully absorbed in the small handbook, "Atlas of Cats," on Friday, during a session seen as a key test of Poland's young democracy.

Lawmakers are to debate controversial changes to the country's justice system, which his Law and Justice party says are needed to reform a broken system but which the European Union sees as a violation of the separation of powers.

Kaczynski, 68, is known as a cat lover, having had cats of his own over the years and helping strays. The trait has somewhat softened the image of a man known for his tough political drive.