Validity and systematicity of newspaper data in event analysis

Methodological work on the use of newspapers for data collection in social movement studies has been based mainly on theoretical postulates rather than empirical research. Using data on public demonstrations in Swiss cities, collected from press and police sources, this article examines how newspapers fare with regard to validity and reliability problems. Newspaper data are shown to result from a combination of news values shared by the journalistic profession and a cultural reproduction process. The first mechanism induces invalid but reliable bias. However, the second creates more problems of comparability across time and space. After having discussed the dominant strategies of data collection, the authors suggest several practical solutions aimed at minimizing and/or neutralizing the problem of bias in newspaper data.