He was a member of Matica hrvatska and was one of the founders of the Croatian Democratic Union in 1989.[2] In 1990 he entered the Croatian Parliament. He served as the Minister of Interior from 31 July 1991 until 15 April 1992. During the Croatian War of Independence he had a rank of Colonel.[3] He was decorated with the Order of Ante Starčević for contribution to the maintenance and development of the Croatian statehood idea, establishment and construction of the sovereign Croatian state,[3][4] while he refused to accept 5 decorations which were awarded to him by President Franjo Tuđman.[3]
Vekić is a critic of post-war policy of Croatian Democratic Union. He entered a conflict with the party's new leaders, Ivo Sanader and Vladimir Šeks. In 2003, after publishing Steps in History - Memories and Events (Croatian: Koraci u povijesti – sjećanja i događaji), where he criticized Šeks, he was expelled from the party.[2]
In May 2011, after a series of adverse events in Croatia, he reshaped his existing civic association "Croatian Guard" into a nationalist political party called the Croatian Guard National Party.[5] He is the President of the party, and they advocate armed training in high schools and capital punishment.[6]
In September 2011 he was accused for war crimes by Serbia, along with Vladimir Šeks, Branimir Glavaš, Tomislav Merčep and 40 other Croatian soldiers involved in the Battle of Vukovar. He is charged with killing of 13 civilians and 6 unidentified persons.[7]