Whenever application for any such writ is made to any officer not residing within the county where the prisoner is detained the officer shall require proof, by oath of the party appearing or by other sufficient evidence, that there is no officer in such county authorized to grant the writ or if there is one that the officer is absent or has refused to grant such writ, or for some cause, to be specifically set forth, is incapable of acting; and if such proof is not produced the application shall be denied.
Wis. Stat. § 782.05