Same-sex marriage in Portugal has been legal since 5 June 2010. The XVIII Constitutional Government of Portugal under Prime Minister José Sócrates introduced a bill for legalization in December 2009. It was passed by the Assembly of the Republic in February 2010, and was declared legally valid by the Portuguese Constitutional Court in April 2010. On 17 May 2010, President Aníbal Cavaco Silva ratified the law, making Portugal the sixth country in Europe and the eighth country in the world to allow same-sex marriage nationwide. The law was published in the Diário da República on 31 May 2010 and became effective on 5 June 2010. Portugal has also recognized same-sex de facto unions, providing several of the rights and benefits of marriage, since 2001. Background De facto unions A de facto union (, ) is a legally recognised union, providing couples, opposite-sex or same-sex, with similar rights and benefits as marriage. Same-sex de facto unions were established by Law no. 7/2001 (Lei n.º 7/2001) in 2001. Constitutional Court ruling On 1 February 2006, a lesbian couple applied for a marriage licence. Their application was refused, but the couple, Teresa Pires and Helena Paixão, promised to challenge the ban in court, saying that it discriminated against them on the basis of their sexual orientation. Discrimination based on sexual orientation is illegal under the Constitution of Portugal. In May 2007, a lower court rejected the motion, and the couple appealed to the Portuguese Constitutional Court. The Constitutional Court received the case in July 2007. Pires and Paixão's lawyer, Luís Grave Rodrigues, presented their arguments on 19 October 2007, including seven legal opinions (pareceres) from Portuguese professors of law arguing that the ban on same-sex marriage was unconstitutional. On 9 July 2009, the Constitutional Court decided on a 3–2 vote that the Constitution did not demand the recognition of same-sex marriage, but also did not oppose it, and that the decision had to be made by the Assembly of the Republic. Legislative action 2008 Two bills to legalize same-sex marriage were presented to Parliament on 10 October 2008. The bills were introduced separately by the Left Bloc (BE) and the Green Party (PEV). Both bills were rejected by Parliament on opposition from the governing Socialist Party (PS) and the main opposition Social Democratic Party (PSD). 2009–2010 Prime Minister José Sócrates said on 18 January 2009 that, if re-elected in the September 2009 elections,