[4] From November 2004 to January 2005 Petir is spokeswoman for the campaign of the President of the Republic of Croatia, Stjepan Mesić in his re-election bid.

[6][7] The antidiscrimination law was opposed by Croatia's Catholic Church, which saw it as a means of promoting homosexuality, but Ivo Sanader's government managed to ensure the consent of all parliamentary parties - including Petir's HSS.

[18][19] In the 2013 local elections, she was defeated in her own hometown, in the municipality of Velika Ludina, where she managed to win only 27 percent of the vote.

[24] Marijana Petir was the organizer of the exhibition "Cardinal Stepinac - Apostle of Hope and Love for God and People" which was held at the European Parliament on June 14, 2016.

The Serbian Foreign Ministry sent protest letters stating that "Stepinac is responsible for cooperating with the Ustasha regime.

[31] Following disputes with the new party leader Krešo Beljak, Petir left the HSS in 2017, continuing to serve as an independent MEP in the EPP group until 2019.