Statutes and Constitutional Conventions are both key inhibitors that prevent complete parliamentary supremacy. Parliamentary supremacy is the idea that Parliament can (in theory) pass any law it wants. This is considered one of the key factors of our parliamentary structure. However, at the same time, we actively seek to inhibit and restrain Parliament through checks and balances. While one of the main forms of this is the separation of power between the executive, legislative and judicial and the idea proposed by Montesquieu in The Spirit of the Laws 1748. The other way this is mitigated is through the use of statutes and constitutional.