 Bulgaria is a parliamentary democracy in which the most powerful executive position is that of prime minister . The political system has three branches — legislative , executive and judicial , with universal suffrage for citizens at least 18 years old . The Constitution of Bulgaria provides also possibilities of direct democracy . Elections are supervised by an independent Central Election Commission that includes members from all major political parties . Parties must register with the commission prior to participating in a national election . Normally , the prime minister @-@ elect is the leader of the party receiving the most votes in parliamentary elections , although this is not always the case . 
