Last week, while America was occupied with elections, an Australian court found Standard & Poor's liable for "misleading" local council governments by awarding AAA rating to derivatives that later lost value (more detail on the case here). Not surprisingly, after the financial crisis, dozens of suits were filed in the United States, Europe, and elsewhere claiming investors were "misled" by the rating agencies. Most of these suits were quickly dismissed or withdrawn. The Australian case is one of the few to find liability.
First, as I documented in a recent Cato Policy Analysis, the regulatory structure for the rating agency is fatally flawed and was without a doubt a contributor to the financial crisis. That said, subjecting rating agencies to legal liability would make the situation worse, not better. From that analysis:
[A] risk from subjecting rating agencies to liability for either their statements or processes is that, in order to protect themselves, the agencies would adopt a “reasonable man” approach. For instance, if the agencies used government forecasts of house prices in their mortgage default models, then it is likely that any court would deem such assumptions “reasonable”; after all, these are the assumptions that regulators rely upon. If such assumptions are, however, grossly in error, as were the housing price forecasts used by various federal agencies, then the value of information created by the rating agencies would also be reduced, if not compromised. A reasonable-man approach would also encourage rating agencies to utilize “consensus forecasts” of key economic variables. Yet the consensus could be dangerously off. The economic forecasting profession does not exactly have a great record at predicting turning points, and it also missed the decline in house prices. A system of liability would likely destroy whatever additional information the rating agencies bring to the market, as the agencies would face tremendous pressure to simply mimic widely held beliefs, which themselves would already be priced into the market.
Another problem would be that rating agencies would most likely face litigation risk from those being downgraded, especially by governments. Witness the abuse Standard & Poor's received from the SEC right after it downgraded the U.S. federal government. Do we truly believe that we would have more accurate ratings if a Greek court were able to decide if a downgrade of Greek government debt was accurate? I would also go as far to argue that ratings of sovereign debt should be considered politically protected speech (but then I'm also for protecting most, if not all, speech).