Premier Colin Barnett has expressed his ‘extreme’ disappointment at yesterday's Supreme Court ruling on the Roe 8 highway project, as the environment minister announced a ‘third party health check’ into the Environmental Protection Authority.

Premier Colin Barnett has expressed his ‘extreme’ disappointment at yesterday's Supreme Court ruling on the Roe 8 highway project, as the environment minister announced a ‘third party health check’ into the Environmental Protection Authority.