National Party MP Chris Finlayson has marked his second term in parliament with an appointment to the dual positions of Attorney General and treaty negotiations minister in Prime Minister elect John Key's new cabinet.

Finlayson has said that a major priority will be to improve the quality of what he described as poorly worded and vague legislation where politicians "did not give proper consideration to the implications of the language they used."

Finlayson was previously a partner at Bell Gully until 2003, when he became a barrister specialising in public law.