Family Staphylinidae.
These beetles carry a defensive secretion (pederin) that can cause serious dermatitis ('whiplash' dermatitis) in humans - see http://www.health.nsw.gov.au/environment/factsheets/Pages/rove-beetles.aspx .
Paederus sp. (genus) is listed in the following regions:
Canberra & Southern Tablelands | South Coast
Maps
Ben Boyd National Park Four WindsPlaces
Edrom, NSW