The Catalan socialists have historically been, while CiU was in power, the largest opposition party in Catalonia. Additionally they have been the strongest force in the metropolitan area of Barcelona, and have held the town hall for many years. They governed Catalonia in a coalition government, which they led, together with ERC and ICV from 2003 to 2010. They are the Catalan branch of the Spanish Socialist Party (PSOE). Historically they were somewhat autonomous in relation to PSOE, but such autonomy has eroded over time. In spite of PSOE opposing it, PSC was in favour of a referendum on independence under the leadership of Pere Navarro as recently as 2014. Traditionally they have spoken out in favour of a constitutional reform that would make Spain more federal. Today, not only do they oppose a referendum, but have been, following instructions from Madrid, key supporters of the application of article 155 of the constitution which suspended Catalan autonomy. They had vowed to never support it. But the PSOE had also vowed never to make Rajoy president; which they did. They have also refused to criticise the imprisonment and prosecution of Catalan ministers and social leaders. Together with Ciutadans and PP they make up the “constitutionalist” or “unionist” block. Under the leadership of Miquel Iceta they obtained 12.7% of the vote and 16 seats in the Catalan parliament in 2015.