Well, if you look at the eNotes page about the themes of The True History of the Kelly Gang, you will see three that strike you: "Post-Colonialism," "The Outlaw as Hero," and "Home and Domesticity." It is the latter that I would like you to consider, because it is here that the stylistic technique of vernacular plays a major role.
The True History of the Kelly Gang, written by Peter Carey, is set in Australia. However, the publisher proclaims the book to be a great American novel based on the fact that the author lived in New York. It is an autobiography of Ned Kelly, whose father was imprisoned and died in an Australian prison when Ned was 12 years old. Ned describes his adventures in adding members to the "The Kelly Gang," and their encounters with the police and judiciary system.
The book is rife with profanity, yet some of this is somewhat muted as Ned cleans up some of the language ostensibly for the benefit of his daughter's reading. It is written in a style termed "vernacular," which uses the language of the setting of the story while keeping true to Ned's Irish language and heritage.
...after we ate we was silent on our blankets looking out across the mighty Great Divide I never seen this country before it were like a fairy story landscape the clear and windy skies was filled with diamonds the jagged black outlines of the ranges were a panorama.
In keeping with the vernacular technique, there is very little punctuation, and essentially no commas throughout the autobiography. This is evident in most any quotation we could choose. However, the reason I chose the quotation above is it combines vernacular with the technique of graphic description, both of which give the novel its beautiful local color.