Romania’s referendum Sunday to change the constitution to define marriage as a union between a man and a woman failed due to lack of voter participation.

The national election bureau reported that only 20.4 percent of Romanian citizens voted in the referendum, which required a 30 percent voter turnout.

The Coalition for the Family, a conservative lobbying group, petitioned the Romanian government for the referendum. The Romanian high court approved the referendum in September. In a press release on Sunday the group blamed a “political boycott” for the referendum’s failure.

Last week Human Rights Watch (HRW) urged Romanian citizens not to vote, calling the referendum “little more than a thinly veiled attempt to scapegoat a vulnerable minority.” HRW said that the potential changes to the constitution violated the European Union’s Charter of Fundamental Human Rights, which bars discrimination on the basis of sexual orientation.

Neither same-sex marriage nor civil partnership are legalized in Romania.

In June the European Court of Justice ruled that Romania must allow the same-sex spouse of an EU citizen to obtain a residency permit.