The APSC has replaced its Interim protocols for online media participation (released December 2008) with Circular 2009/6: Protocols for online media participation.
The new Circular is briefer than its predecessor, going further than I had expected, making it clear in no uncertain tones that (my bold in the quote below),
Web 2.0 provides public servants with unprecedented opportunities to open up government decision making and implementation to contributions from the community. In a professional and respectful manner, APS employees should engage in robust policy conversations.This guidance is followed by a set of ground rules - which are consistent with the practice of many other organisations. You can read them in the Circular.
Equally, as citizens, APS employees should also embrace the opportunity to add to the mix of opinions contributing to sound, sustainable policies and service delivery approaches. Employees should also consider carefully whether they should identify themselves as either an APS employee or an employee of their agency.
In case your agency need to consider the Circular within the APS code, the APSC says that,
The guidance has been incorporated into chapters 3 and 15 of APS Values and Code of Conduct in practice: A guide for APS employees and Agency Heads. This publication assists APS employees to understand the practical application of the APS Values and Code of Conduct in both common and unusual circumstances. It also provides advice for agency heads in establishing policies and procedures that promote the APS Values and ensure compliance with the Code. A revised edition of the publication is now available on the Commission’s website at www.apsc.gov.au/ethics/publications.html.
With the "can I/Can't I" of online participation now much clearer, the next step for agencies is to ensure they put the best possible social media participation guidance in place to address any grey areas.
If your agency wants to consider some examples of best practice social media policies, there are over a hundred examples at Social Media Governance.