After his appointment as the NAC chairman for the Northern Territory, Forrester was put on the subcommittee in charge of drafting the "Makarrata" proposal. The proposal was for a treaty that recognised the sovereignty of Aboriginal nations in Australia. People wanted the government of Australia to deal with Aboriginal nations as it would deal with another sovereign nation under international law. Through the 1980s, the support for this treaty amongst Aboriginal people grew steadily. After talking with Aboriginal communities in his home region, Forrester was convinced that his people were in favour of a treaty. He argued, however, that the negotiations should be done under the oversight of the United Nations.