In the 2008 federal election, he was elected to represent the riding of Papineau in the House of Commons. In 2009, he was appointed the Liberal Party's critic for youth and multiculturalism, and the following year, became critic for citizenship and immigration. In 2011, he was appointed as critic for secondary education and sport. Trudeau won the leadership of the Liberal Party in April 2013 and led his party to victory in the 2015 federal election, moving the third-placed Liberals from 36 seats to 184 seats, the largest-ever numerical increase by a party in a Canadian federal election. As Prime Minister, major government initiatives he undertook during his first term included legalizing recreational marijuana through the Cannabis Act; attempting Senate appointment reform by establishing the Independent Advisory Board for Senate Appointments; establishing the federal carbon tax and negotiating trade deals such as the United States-Mexico-Canada Agreement and the Comprehensive and Progressive Agreement for Trans-Pacific Partnership; while later grappling with controversies surrounding the SNC-Lavalin affair.