I agree with the other Expert that there are attorneys who might represent you in your divorce proceedings pro bono - no fee to you (it literally means "for the public good"), or other agencies, like Legal Aid that will assist you in filing for divorce, but not based upon the fact that your husband is incarcerated.
And, as the other Expert said, there is still the matter of Court filing fees, which will not be waived simply because your husband is incarcerated.
However, if you feel you do not have the funds to pay the Court's filing fees, one avenue worth pursuing is to go to the Office of the Court Clerk ( Or Office of the Prothonotary, or any other name given to this Office in your jurisdiction) where Complaints, Petitions, Motions and other Pleadings are filed and their respective Fees paid, and ask if you qualify to proceed IN FORMA PAUPERIS; You would then file a Petiton to Proceed in Forma Pauperis. Your Petition would state the reasons you cannot afford the filing fees. This, too, has nothing to do with the fact that your husband is incarcerated; it is based solely on your inabilty to pay the filing fees.
In Some jurisdictions, it is the Prothonotary who makes this determination, in others, the Petition is brought before a judge who makes this determinatin. If the Clerk or judge determines that you are unable to afford the filing and other Cour fees, your Petition will be granted and these fees will be waived in your case.
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