Ethics is a branch of philosophy that is concerned with issues of right or wrong. The use of photography as photojournalism raises a number of ethical issues with regard to how the subject should be treated and represented. The United States (US) photographer James Nachtwey has made a reputation for himself by photographing war and humanitarian disasters. Meta-ethics is concerned with the origins and meaning of ethical issues. One area of concern for ethical issues is the manipulation of digital photographs. Subject to the justification by overriding considerations of the public interest, a journalist shall do nothing which entails intrusion into private grief and distress. A. D. Coleman refers to an incident where a freelance photographer, Gianfranco Gorgoni, took a street photograph in New York. During the 1860s photographs of dead bodies from the American Civil War were in great public demand, yet the public whose motivations were probably voyeuristic were not in accord with the intentions of the photographer.