Curvilinear disparity

The Special Law of Curvilinear Disparity or May's Law is a theory conceived in 1973 by political scientist John D. May in his publication Opinion Structure of Political Parties. The theory posits that the rank and file members of a political party tend to be more ideologically extreme than both the leadership of that party and its voters. May contends that politically active people can be classified into three major strata or echelons according to their relative status within a party; party elite, middle-elite, and non-elite. Members of each divergent strata have contrasting motivations for being politically active and calibrate their ideological stances to differing extents as a result.

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