Political protection: The case of large-scale oil spills and the stock prices of energy firms

In this study, we utilize a sample of publicly traded US energy firms to investigate the stock market responses to 40 large-scale oil spills. Our findings reveal that the stock prices of extraction and refining firms experience significant declines during the periods surrounding these oil spill incidents, and energy pipeline firms exhibit a relatively smaller decrease. These results underscore the risk exposure shared by all energy firms, irrespective of their direct involvement in the oil spill incident. Furthermore, our study uncovers an intriguing dynamic—the influence of political connections established through lobbying activities. We observe that these political ties serve to significantly mitigate the negative market reactions to oil spills. Our results suggest that, from the market's perspective, firms with political connections are less vulnerable to the impending costs associated with oil spills when compared to their non-politically connected counterparts.