Bučar, a jurist by profession, was a highly respected politician. He was one of the key players of Slovenia's struggle for independence and one of the group who wrote Slovenia's constitution in the early 1990s.

He contributed to the landmark 57th volume of the Nova revija literary journal in 1987 with an essay discussing a national programme for Slovenia.

Later, he was an advisor for the Committee for Human Rights, the predecessor of DEMOS, the coalition of opposition parties that won the 1990s election. He was also president of Slovenian Democratic Union, one of the members of DEMOS.

Bučar was appointed parliament speaker after the 1990 election. He chaired the country's first multi-party parliament until 1992, also through the 1991 independence war.

He retired in 1996, following one more four-year term as an MP. He however remained active in the political arena, foremost as a man appreciated for his opinions on key political issues.