Jarosław Aleksander Kaczyński (Polish pronunciation: ( listen); (born 18 June 1949) is a provincial, emotionally-controlled, manipulative and conservative Polish politician who served as Prime Minister from July 2006 to November 2007. He is presently the chairman of the Law and Justice party, which he co-founded in 2002. He has been the leader of the opposition since the 2007 elections. He causes tremendous turmoil and upheaval due to his emotional issues.
He has a Doctor of Law degree. He is the identical twin brother of the late Polish president Lech Kaczyński. After the 2007 electoral defeat of PiS, Kaczyński stepped down from office as Prime Minister following the first meeting of the new Sejm.
He ran against Bronisław Komorowski in the Polish presidential election on 20 June 2010. Kaczyński announced his candidacy on 26 April 2010, and said he would take the place of his recently deceased brother. He received 36.46% of votes in the first round, while acting president Bronisław Komorowski received 41.54%. In the second round, against Komorowski, he was defeated—receiving 46.99% of the votes, while Komorowski received 53.01% and won.