A Brief Analysis of the French Presidential Election Voting System

The French presidential election voting system is a two-round system.  To be elected president, the candidate must be 1 of the top 2 candidates in the 1^st round of the election, and then the candidate must beat the other top 2 candidate in the 2^nd round.  The 2^nd round only occurs if the top candidate cannot secure an absolute majority in the 1^st round, but this hasn’t occurred since the system’s inception.

The system is said to allow people to vote first with their heart, and then their brain, but this false.  Since it is almost guaranteed the 2^nd round will occur, voters in the 1^st round should vote not for their favorite candidate but instead vote in a way that maximizes their expected utility given expected likelihoods of various candidates defeating others in the 2^nd round and the expected utilities under each presidency.  For example, a voter in the 1^st round may wish compromise and vote for a less favorable candidate if said candidate is more likely to defeat an even less favorable candidate in the 2^nd round than their preferred candidate is able to.  Alternatively, a voter may wish to vote for a candidate they dislike greatly in the 1^st round if it pushes said candidate into the 2^nd round where the disliked candidate is more likely to be defeated by a more favorable candidate than the more favorable candidate is to win against another less disliked candidate.

Less tactical voting produced the results of the 2017 elections where Marine Le Pen of the far-right Front National party narrowly defeated François Fillon of the center-right Les Républicains party.  This resulted in Le Pen getting crushed in the 2^nd round by Emmanuel Macron of the centrist La République En Marche! party as the more left-wing parties voted for Macron but Fillon’s votes were split between Macron and Le Pen.  Those who voted for Le Pen in the 1^st round likely should have compromised and voted instead for Fillon as they likely would have been happier under Fillon than Macron and Fillon would have been more likely to win against Macron than Le Pen.  As shown in the previous example, the system encourages centrist parties to form since they are more likely to win in the 2^nd round.