Flip-Flopping in a Representative Democracy

The vote in the House of Commons, on February 1st, 2017, about whether the United Kingdom should leave the European Union raises a host of important theoretical questions in normative political theory. One of them is this:
Main Question: In a representative democracy, can a member of a legislature legitimately flip-flop and vote in accordance with the majority view on Issue when she, prior to getting knowledge, through a referendum result, of what the majority view is on Issue, has defended, and recommended to voters, a view that is logically inconsistent with the majority view?
This paper defends an affirmative answer to the Main Question. This conclusion is not trivial given that there are many ways in which a member of a legislature can engage in an act of illegitimate flip-flopping. The last section of the paper moves beyond the Main Question and the related issue of how a legislator can legitimately flip-flop. This section raises the question of whether the trustee view of what obligations a legislator has in a representative democracy towards her constituents is mistaken. An alternative to the trustee view is presented and discussed, and it is concluded that this alternative view is implausible.