For the less educated, a definition of a poltroon. It is a noun (and not used much now adays) and means = a complete coward. It is from the Old Italian word, poltrone, which means a lazy good-for-nothing
As it relates to the Zouaves, I understand the the US Congress had a standing committee at that time to look into such 'war crimes.' I have had the dickens of a time finding the reports from this committee. Anyone else have any good luck?