Sentence adjustment

I am a little surprised that yesterday's letter appeared in the Advertiser this morning. It dealt with the issue of the sentencing of a man convicted of manslaughter. He identifies himself as 'aboriginal' and this was taken into consideration.
I have serious reservations about this. There are perhaps times when it would be appropriate, especially for an indigenous Australian of full blood descent living on native lands who speaks little or no English. It is surely less so when the individual in question is clearly not of full blood descent, speaks English and has been convicted of lashing out in anger. Were it not for the identification as 'aboriginal' the sentence would have been much longer.
The question therefore arises, where do we draw the line when giving what amounts to special consideration? If we allow this to happen to a person who identifies as 'aboriginal' do we also allow it for an immigrant, or the child or grandchild of immigrants? Do we allow it for those from abusive households - or just abusive households who are at the lowest end of the economic scale? Do we allow it for those with social, intellectual, psychological or physical disabilities? Do we allow it for someone who has been taunted over the circumstances of some other family member?
I suspect that the courts and the government have opened a can of highly poisonous snakes here.