Those concerned for protection of the environment are sometimes threatened with legal action when they speak out on controversial environmental issues. This can have the undesirable effect of stifling community debate.

The Defamation Act 2005 came into force in WA on 1 January 2006. This Act, along with Acts in other States and Territories, has unified the law of defamation in Australia. In particular, a number of defences to defamation are now set out in legislation, although common law defences still apply where there is no inconsistency. This fact sheet encourages responsible free speech on environmental issues by providing a brief outline of the law of defamation, including the reforms in the Defamation Act 2005. Note that statements made before 1 January 2006 are not subject to the Defamation Act 2005.