ERC would support the CiU on sovereignty issues while on other matters it might oppose it. The two leaders drafted the Declaration of Sovereignty and of the Right to Decide of the Catalan People, which was adopted by the parliament at its first sitting in January 2013. The declaration stated that "the Catalan people have, for reasons of democratic legitimacy, the nature of a sovereign political and legal subject", and that the people had the right to decide their own political future. The Spanish government referred the declaration to the Spanish Constitutional Court, which ruled in March 2014 that the declaration of sovereignty was unconstitutional. The court did not, however, reject the "right to decide", arguing that that right didn't necessarily imply sovereignty or self-determination. On 11 September 2013, an estimated 1.6 million demonstrators formed a human chain, the Catalan Way, from the French border to the regional border with Valencia. The following month, the CiU, the ERC, the ICV-EUiA and Candidatura d'Unitat Popular (CUP) agreed to hold the independence referendum on 9 November 2014, and that it would ask two questions: "Do you want Catalonia to become a State?" and (if yes) "Do you want this State to be independent?". A further mass demonstration, the Catalan Way 2014, took place on 11 September 2014, when protesters wearing the Catalan colours of yellow and red filled two of Barcelona's avenues to form a giant "V", to call for a vote. Following the Constitutional Court's ruling, the Catalan government changed the vote to a "process of citizen participation" and announced that it would be supervised by volunteers. The Spanish government again appealed to the Constitutional Court, which suspended the process pending the appeal, but the vote went ahead. The result was an 81% vote for yes-yes, but the turnout was only 42%, which could be seen as a majority opposed to both independence and the referendum. Criminal charges were subsequently brought against Mas and others for defying the court order. In June 2015 the CiU broke up as a result of disagreement between its constituent parties – Convergència Democràtica de Catalunya (CDC) and Unió Democràtica de Catalunya (UDC) – over the independence process. Mas's CDC joined with the ERC and other groups to form Junts pel Sí (Together for "Yes"), which announced that it would declare independence if it won the election scheduled for September. In the September election, Junts pel