Bob, Zabriskie was the United States Disrict Attorney for the Territory of Arizona at that time. Actually, Zabriskie was named to that position a few days after Ringo's death if my memory is correct.
Here is a great article on Joseph C. Tiffany... If you haven't used the site in the link before, just register a username and password and you can read the article for free.
https://www.jstor.org/stable/41695290