This paper [ungated; longer version] has it all: a design based on a ‘natural experiment’, recently declassified East German public opinion surveys, and a counterintuitive result – exposure to West German TV increased support for the the East German communist regime. Here is the abstract:
In this case study of the impact of West German television on public support for the East German communist regime, we evaluate the conventional wisdom in the democratization literature that foreign mass media undermine authoritarian rule. We exploit formerly classified survey data and a natural experiment to identify the effect of foreign media exposure using instrumental variable estimators. Contrary to conventional wisdom, East Germans exposed to West German television were more satisfied with life in East Germany and more supportive of the East German regime. To explain this surprising finding, we show that East Germans used West German television primarily as a source of entertainment. Behavioral data on regional patterns in exit visa applications and archival evidence on the reaction of the East German regime to the availability of West German television corroborate this result.
The ‘randomization’ is based on the fact that the penetration of West German TV in East Germany was determined by topographical features. The area around Dresden is the main one which had no access so it serves to anchor the comparisons.
The effect sizes reported in the empirical analysis are not great – the different models and estimators show a positive effect of exposure to West German TV in the range of 0.15 to 0.26 on a 4-point scale of support for the East German communist regime (survey data gathered in 1988/1989 among young people). But even if we take the empirical findings to imply that exposure to West German TV definitely did not decrease support for the communist regime, the conclusions are important and significant. The mechanism proposed to explain the counterintuitive findings is that watching West German TV actually made life more bearable and provided an escape from the dull communist reality.
One of the authors has another piece using a very similar setup based again on the natural experiment of West German TV penetration in which he argues that West German TV exposure did not affect participation in the protest participation in the East German Revolution in 1989.