 Behrendt is the director of the St. George Women's Housing Inc. From 2009 to 2012, she co-chaired the City of Sydney's Aboriginal and Torres Strait Islander Advisory Panel.She is an active member of the Metropolitan Local Aboriginal Land Council.Behrendt has been involved in several pro bono test cases involving adverse treatment of Aboriginal peoples in the criminal justice system, including appearing as junior counsel in the NSW Supreme Court case of "Campbell v Director of Public Prosecutions" [2008].