Controversial changes to the Act (the "GCSB Bill") were announced by Prime Minister John Key in May 2013.

The intention of the GCSB Bill was to update the GCSB statutory framework to respond to the changing security environment and public law environment, and to enhance the external oversight mechanisms that apply to the intelligence agencies by strengthening the office of the Inspector-General of Intelligence and Security and by improving the operation of Parliament's Intelligence and Security Committee.

[3] Dame Anne Salmond, who is a distinguished professor at the University of Auckland and the then New Zealander of the Year, condemned the legislation as being in breach of the Bill of Rights.

[3] Protests were held around the country in July and August 2013, with speakers at one event in Auckland including Salmond, unionist Helen Kelly and Internet tycoon Kim Dotcom, who had previously been illegally spied on by the GCSB.

[7] Former Labour deputy prime minister Sir Michael Cullen and future governor-general Dame Patsy Reddy were appointed as independent reviewers.