Use of anonymous sources as an ethical resource: a criterion for journalistic quality?

What are the guidelines for the use of anonymous sources in journalistic coverage, what are their functions and what are their relationships with journalistic quality? This paper investigates what are the concepts and propositions of research in Journalism in Portuguese on the use of anonymous sources in journalism, especially with regard to ethical implications. To answer this question, eight articles, six books and a master's thesis with a theoretical approach on sources and anonymous sources were evaluated, submitted to non-categorical content analysis. As a result, it was identified that research in Journalism in Portuguese is little or almost not dedicated to a deeper reflection on the ethical implications of the use of anonymous sources and also does not evaluate its impacts in a more consistent way on journalistic quality.