I have to report that my searching today at SAGHS turned up absolutely nothing. I managed to book a computer for an hour, and did as many different searches of the South Australian Police Gazettes as I could.
I searched the years between 1866 and 1876, and I searched by Turner, Osbald*, Edwin only, and just using the term murder in the search engine. Unless he was using yet another name, there was no mention.
Didn't think to search using "Theft" but expect there would have been too many results to wade through anyway.
One point.....there were absolutely no results for the search of "Edwin" until 1870, and no murders before that year either. So I am wondering how much detail was in the earlier Gazettes. (I know that once you find a name and then use the microfiche to look at the actual page, you can get some amazing information from 1880 onwards.......)
There was no murder committed by an Edwin.....just one by an Edward Wilson in 1872.

Dee