If you are successful in finding a lawyer that will take the criminal appeal case on a pro bono basis, that lawyer can file to substitute as counsel. Your fiance can hire a lawyer to work with the appointed public defender appeal attorney on the appeal, or replace the appointed attorney if the court agrees. Get moving quickly so that the attorney your fiance wants to represent him gets into the appeal case as soon as possible. Alert the court of this desire and coordinate with the appointed attorney to do so right away.
You might find my Legal Guide helpful "Ethics: Yes I Need a Lawyer!"
You need a lawyer. Check with a lawyer in your locale to discuss more of the details.
Good luck to you.
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It's very hard to get a cheap or free lawyer to do an appeal, and your fiance's court appointed lawyer may be a better bet, as they're very experienced and know what's they're doing. Try legal aid, linked below.
Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.
In an 80-life case, even if you found an attorney willing to work for minimum wage, it would cost thousands of dollars to read all of the transcripts, do the necessary research and draft the necessary legal documents.
His attorney would be appointed through the California Appellate Project, which contracts with attorneys to handle appeals. They're paid about a hundred dollars an hour for their time.
Why do you think someone else will do a better job for little or no money?