SAN JOSE, Costa Rica — Conservative Costa Rican lawmakers are getting a lesson in the importance of reading the fine print.
They were mortified Friday to learn they may have accidentally approved language making same-sex unions legal when they passed a piece of legislation this week.
President Laura Chinchilla Thursday signed the bill governing social services and marriages for young people.
The mostly conservative members of Congress did not notice that the final version of the bill had changed earlier language that defined marriage as a union between a man and a woman.
After realizing they had approved a bill that ‘‘confers social rights and benefits of a civil union, free from discrimination,’’ the lawmakers asked Chinchilla to veto the new law.
The change to the bill was proposed by leftist lawmaker Jose Villalta of the Broad Front Party, who said it was passed unanimously.
‘‘The problem is that there are lawmakers who don’t read what they are voting on,’’ Villalta said.