For legal materials, Chicago recommends using the The Bluebook: A Uniform System of Citation (see 14.269). It also states:
The Bluebook and the ALWD Guide are used in the United States. For citation guides used in Canada, see 14.293; for those used in the United Kingdom, see 14.297.
Following the broad principle of using citation styles used within a specific jurisdiction, we recommend using the Australian Guide to Legal Citation 4th edition when citing legal materials.