The following letter to the editor of The Australian was submitted on 21 June 2011:
As I told your Canberra reporter on 20 June 2011, but you did not report to your readers, the difference between action on a republic and climate change is that the former requires a change to the Constitution and the latter requires a decision by the Parliament, as already empowered by the Constitution. The former requires a plebiscite and referendum, the latter requires neither - if you believe in the responsibility of Parliament.
Senator Bob Brown
Australian Greens Leader