On 11 November 1999 the High Court reserved its decision on a constitutional challenge by the CFMEU against the award simplification transitional provisions of the Workplace Relations and Other Legislation Amendment Act 1996(WROLA). The challenge related to items 50 and 51 of the WROLA Act, and to the removal of non-allowable matters from Federal awards.

Supported by the States of NSW, Victoria and Queensland, the CFMEU submitted that the transitional provisions enabled Parliament to directly alter the terms and conditions of employment contained in federal awards. This, it was argued, was outside the scope of 51(xxxv) of the Constitution, which limits Parliament from directly legislating the terms and conditions of employment of federal award employees. To this end the CFMEU argued that items 50 and 51 were invalid. Items 50 and 51 are not laws for the prevention and settlement of disputes by conciliation and arbitration. Parliament, the CFMEU contended, cannot intrude, industrial disputes must be prevented or settled by conciliation and arbitration, and there is no room for Parliament to come in and say "Yes, except for this or that bit". The Federal Government argued that to exclude certain matters from awards was not directly legislating on conditions of employment.

A decision is not expected for some months. If the challenge is successful, it is difficult to speculate on the nature of the orders the High Court would make. To simply reinstate those award provisions that have been removed in the simplification process would be practically involved and complex.