The term 'law' generally has a very broad application and consists of the following components:
• strictly legal requirements, emanating from both the common law and statute law, which Parliament has power to change
• policy requirements, which are not enacted in laws, but may take the form of directives from government departments that directly or indirectly impact on specifications or project viability
• regulatory requirements set by an independent regulator deriving its powers from statute law. Government has ultimate control over regulators through parliament's power to change the law, but their operation is otherwise self-sufficient.