In 1968, Wilson promoted Castle to become First Secretary of State, the second-most senior member of the Cabinet, as well as Secretary of State for Employment. In the latter role, Castle fiercely advocated for the passage of the "In Place of Strife" legislation which would have greatly overhauled the operating framework for British trade union. The proposal split the Cabinet, and was eventually withdrawn. Castle was also notable for her successful intervention over the strike by Ford sewing machinists against gender pay discrimination, speaking out in support of the strikers, and overseeing the passage of the Equal Pay Act. After Labour unexpectedly lost the 1970 election, some blamed Castle's role in the debate over trade union for the defeat, a charge she resisted.