In a particularly important area the Senate is on exactly the same footing as the National Assembly. This exception concerns changes to the Constitution.

If a bill is tabled to amend the constitution, the government cannot override the opposition of the Senate. The Shuttle must continue until the two houses adopt an identical text. The same rule applies to changes in certain organic laws.

A bill to revise the constitution is finally adopted only after being approved by referendum or by the membership of both the National Assembly and Senate in a joint session known as Congress. A majority of three-fifths of votes cast by the Congress participants is required to enact the change.