Politics & Government
Executive–Legislative Relations under Cohabitation in Semi-Presidential Systems
Quick fact
In the French Fifth Republic, cohabitation occurred three times (1986–88, 1993–95, 1997–2002) because the president's party lost the parliamentary majority, forcing the president to appoint a prime minister from the opposition. During these periods, the president’s domestic policy power was largely ceded to the prime minister, who commanded the legislative majority.
Why this is interesting
What happens when a president and a prime minister are from opposing parties? In some countries, they must govern together—a situation called cohabitation—and the result is a power struggle that reshapes the entire executive branch.
Read the full explanation
Understanding Executive–Legislative Relations under Cohabitation in Semi-Presidential Systems
To understand cohabitation, you first need to see how a semi-presidential system divides power. Unlike a pure presidential system (like the US) where the president is both head of state and head of government, a semi-presidential system has both a directly elected president and a prime minister who is responsible to the parliament. Normally, when the president's party also controls the legislature, the president dominates, and the prime minister is a loyal subordinate. But cohabitation occurs when the president's party loses the legislative election, and the opposition wins a majority. Then, the president must appoint a prime minister from that majority. Suddenly, the prime minister has the support of the legislature, while the president—though still head of state—loses the ability to set the domestic agenda. The constitution gives the president some powers (like foreign policy and defense) but leaves the prime minister in charge of most day-to-day governance. The result is a complex dance of cooperation and conflict: the two executives must work together, but their political goals are often opposed. You can think of it like a CEO (president) who stays on as a figurehead while the board (legislature) empowers a new general manager (prime minister). The CEO still signs off on big contracts, but the manager runs the company.
A deeper explanation
The mechanism behind cohabitation lies in the constitution's allocation of powers and the political reality of party competition. Semi-presidential constitutions, such as France's, are often ambiguous: the president is powerful when they have a loyal majority (a 'presidential' reading), but when the opposition controls the legislature, the constitution tilts toward a 'prime-ministerial' reading. The key is that the prime minister is accountable to the legislature, and the president's appointment power is constrained by the need to appoint someone who can command a majority. Under cohabitation, the prime minister can pass legislation and control the executive agenda, while the president retains formal powers like dissolving the parliament (but often refrains from using them because it could backfire) and a role in foreign policy (the 'reserved domain'). The president's ability to influence domestic policy is sharply reduced, but they can still shape international relations and serve as a constitutional check. This dynamic is the central mechanism: the dual executive, which is designed for unity, becomes a site of tension when party loyalties diverge. Cohabitation thus reveals the inherent contestability of semi-presidentialism—the same constitutional text can be interpreted in radically different ways depending on the electoral outcome. Understanding this helps explain why some presidents become marginalized and how institutional rules adapt to unexpected political outcomes.