The British Labour Party is a creation of the country’s trades-union movement. The trades unions are still a crucial part of the party’s extra-parliamentary organization. In addition, the trades unions still sponsor a number of Labour party candidates and Members of Parliament. Within the Parliamentary Labour Party, union members are organized in the ‘Trade Union Group of Labour MPs’. Despite the close organizational links between the trades unions and the Parliamentary Labour Party and the fact that the Labour Party was in government between 1997 and 2010, working-class interests have been underrepresented in parliamentary politics. This includes legislative initiatives, speeches and parliamentary questions. This paper is divided into two parts. First, we will employ methods of quantitative text analysis to a corpus of parliamentary questions for written answer covering the Parliaments of 2001-2005, 2005-2010 and 2010-2015 to assess the impact of MPs affiliated with, or sponsored by, trades unions on the extent to which the Parliamentary Labour Party represents working-class interests. Second, we will use this longitudinal dataset to explore the extent to which longer-term parliamentary socialization gradually reduces the representation of working-class interests amongst trades-union members (i.e., Members of the Parliamentary Labour Party grow more alike over time), or whether the frequently-observed distance between the Parliamentary Labour Party and the trades-union movement is caused by selection effects during the process of candidate nomination.
