▁ 1 9 6 5 ▁International ▁Convention ▁on ▁the ▁El im ination ▁of ▁All ▁Form s ▁of ▁Ra cial ▁Disc rim ination , ▁which ▁Australia ▁rat ified ▁in ▁September ▁ 1 9 7 5 . ▁The ▁High ▁Court ▁of ▁Australia ▁confirmed ▁that ▁the ▁external ▁affairs ▁power ▁was ▁a ▁valid ▁source ▁of ▁power ▁for ▁the ▁R DA ▁in ▁Ko ow arta ▁v . ▁B jel ke - P eters en , ▁and ▁again ▁in ▁M ab o ▁v ▁Queensland ▁( No ▁ 1 ). ▁ ▁While ▁the ▁A H RC ▁maintain s ▁that ▁the ▁R DA ▁provides ▁an ▁appropriate ▁balance ▁between ▁freedom ▁of ▁speech ▁and ▁freedom ▁from ▁ra cial ▁vil ification , ▁some ▁legal ▁academ ics ▁have ▁suggested ▁that ▁section ▁ 1 8 C ▁of ▁the ▁R DA ▁( see ▁below ) ▁may ▁be ▁un const itution al , ▁on ▁the ▁basis ▁that ▁it ▁is ▁incons istent ▁with ▁the ▁constitution al ▁imp lied ▁freedom ▁of ▁political ▁communication . ▁ ▁S cope ▁of ▁the ▁Act ▁ ▁Pro hib ition ▁of ▁ra cial ▁disc rim ination ▁in ▁certain ▁context s ▁ ▁Ra cial ▁disc rim ination ▁occurs ▁under ▁the ▁R DA ▁when ▁someone ▁is ▁treated ▁less ▁fairly ▁than ▁someone ▁else ▁in ▁a ▁similar ▁situation ▁because ▁of ▁their ▁race , ▁colour , ▁descent ▁or ▁national ▁or ▁eth nic ▁origin . ▁Ra cial ▁disc rim ination ▁can ▁also ▁occur ▁when ▁a ▁policy ▁or ▁rule ▁appears ▁to ▁treat ▁everyone ▁in ▁the ▁same ▁way ▁but ▁actually ▁has ▁an ▁unf air ▁effect ▁on ▁more ▁people ▁of ▁a ▁particular ▁race , ▁colour