Van Vugt, M., Van Lange, P. A. M., Meertens, R. M. and Joireman, J. A. (1996). Why structural solutions to social dilemmas might fail: A field experiment on the first carpool priority lane in Europe (link).  Social Psychology Quarterly, 59 , 364-374.

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Abstract:

In the current field experiment we evaluate a structural solution to a real-life social dilemma by examining the effects o f a carpool priority lane on judgments and preferences concerning the decision to commute by carpool (i.e., the presumed cooperative option) or driving alone (i.e., the presumed noncooperative option). Our general hypothesis was that this intervention would evoke a process o f self-justification in solo drivers, arising from feelings of relative deprivation andlor cognitive dissonance. Consistent with predictions, we found that in comparison with judgments made before the implementation ofthe carpoollane, solo drivers tended to decrease the importance of an attribute inherently linked to carpooling (i.e., low travel costs) and to increase the importance of an attribute inherently linked to driving alone (i.e., flexibility). Moreover, solo drivers exhibited a weaker preference for ca/pooling after the establishment of the ca/pool lane. This finding suggests that the negative side effects of this structural measure were more pronounced than the intended ca/pool-promoting effects.