According to the constitution, the legislative powers are exercised by the Parliament, the governmental powers are exercised by the President of the Republic and the Government, and the judicial powers are exercised by government-independent courts of law. The Supreme Court may request legislation that interprets or modifies existing laws.
The Government (i.e. executive) is responsible to and must maintain the confidence of the elected House of Commons. Although the two chambers formally have many of the same powers, this accountability clearly makes the Commons dominant—determining which party is in power, approving its proposed budget and (largely) the laws enacted.