As Australia is a rich country, the major issues of social justice and equity raised by its trade have to do with the conditions that workers experience in the countries with which Australia trades. This issue was highlighted by the recent disaster in the clothing factory in Bangladesh.
Rich countries tend to get many of their imports from poor countries. Over the years, the jobs that pay the least and that take the least skill have left the rich countries and gone to the poor countries. There, they can be done by workers who demand much lower salaries. This allows the people in the rich countries to buy imported goods for very low prices.
This brings up an issue of social justice and equity. Should people in rich countries exploit the labor of people working in poor countries, often for low pay and in bad conditions? Is it wrong to save money in this way or is it actually a good thing to buy from poorer countries on the idea that without trade the people in those countries would have fewer prospects than they do now?