Yes, well with a "
conditional pardon", he was free, BUT with the condition he could not leave Australia.
Australia is a big place, and many ex-convicts went on to make a success of their lives - finding stable work, taking a new wife and having a family. It was not un-common for some of them to head for the gold fields to try their luck.
There are some mentions of Thomas Field in the WA newspapers during his ticket of leave time when he was fined for being out too late. Nothing too serious.
https://trove.nla.gov.au/newspaper/article/3174154?searchTerm=%22Thomas%20Field%22https://trove.nla.gov.au/newspaper/article/65484598?searchTerm=%22Thomas%20Field%22https://trove.nla.gov.au/newspaper/article/65484731?searchTerm=%22Thomas%20Field%22After that, there is no further mention of him in Western Australia, so my guess is that he moved to another state in Australia. I haven't looked for him at all elsewhere in Australia.
I suggest you might start a new thread about Thomas FIELD on the Australian Board.
Be sure to provide ALL the information (birth details, parents, wife and children, convict details) so that time is not wasted repeating research already done.--------------------------
The other question that you might want to look into is what happened to Thomas' young wife, Mary Field (nee Duck). What was her family background? Did she marry again? We know (from her son's tattoo) that by 1873 she had died. What happened to her other children?
There are so many questions to research for your interesting family.

Enjoy!
As this thread really started out finding the parents of Joseph Brooks born 1915, and has now become very long, it might be best to start new threads for other lines of enquiry. Remember to include a link back to here, and to provide all the information you already know, and what you want help to find.
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I provided in above posts links to very good / important records for you, because I know they are
not on Ancestry. Importantly, remember that not everything is on Ancestry.
You will find on Ancestry convict / prison records, etc; as well as all the Workhouse and Poor Law records, ships lists, but not Joseph Field's Navy record.
I would take your time to collect all those records, and read through them to get a real understanding of your family history.
We are always willing to help, so come back and ask, or let us know how you are going.