Firstly it is a vague concept, yet regular law indicates that common law principles of individual liberty shall preside over any legislation. This is contrary to modern reality as in most western democracys today statutes have greater legal force.
This is how it should be as parliament is held accountable through:
- Internal statutory controls (own rules within house)
- judicial controls ( i.e. judicial review for where there is failure to abide by statutory rules)
- External statutory controls (Bill of rights acts, human rights acts, Ombudsmen and so on)
- Political accountability (ministers are elected so are held accountable through the public)

Also, legislation is made through the democratically elected ministers while the common law is created through judicial precedent - judges are appointed not elected.

Furthermore, most common law principles have been codified in to statutes, namely those concerning indvidual rights and libertys - so there is harmony between the two sources of law in how they supplement each other.