The UK Natural Environment Research Council (NERC) recently released a study on public opinion regarding geoengineering titled Experiment Earth?. One of the more interesting findings pertains to the "moral hazard" argument against geoengineering, that is, people will embrace geoengineering as an excuse to avoid emissions reductions, and current levels of fossil fuel consumption will persist if not increase. Moral hazard has emerged as one of the principal arguments against climate engineering, despite the fact that geoengineering advocates generally support aggressive mitigation as the preferred option, and are quick to note the limitations of specific strategies, such as continued ocean acidification and the so-called "termination problem" in the case of stratospheric aerosol injections.
Evidence from the public dialogue summarized in the NERC report indicates that participants viewed mitigation and geoengineering as complementary policies, not as mutually exclusive alternatives. Stakeholders saw a link between geoengineering and emissions controls, and preferred a suite of mitigation and geoengineering measures to reliance on any single approach. "This evidence is contrary to the 'moral hazard' argument that geoengineering would undermine popular support for mitigation or adaptation," notes the report. While this study represents only one set of empirical data gathered in one particular sociocultural context, it is to my knowledge the first time the moral hazard argument has been tested, and demonstrates little support for this proposition.
(As a side note, I am currently polishing a chapter/article for publication that takes on another major argument against geoengineering, the supposed threat of unilateral deployment. I contend that the threat of unilateralism is a myth, and that climate engineering is in fact governed by a multilateral logic.)