Participation bias, durable opinion shifts and sabotage through withdrawal in citizens' juries

We analyse a citizens' jury experiment held in Dublin on the 'hot-button' issue of waste incineration. The jury was a random sample drawn from the 2002 Irish Election Study (IES), and we compare jurors to non-jurors in the 2002 IES, and in 2003 and 2004 panel studies. Large opinion shifts were observed in a representative jury; these shifts remained observable nine months later. However, as a direct consequence of our choice of a contested issue, the jurors' verdict was framed by the unwillingness of key stakeholders to participate. Stakeholders who expect to be on the 'losing' side, including public representatives and officials, may obstruct and delegitimise citizens' juries by withholding participation. This informal gatekeeping power undermines the potential of citizens' juries to empower citizens.