The case of Jo Anne B. Barnhart, Commissioner of Social Security v. Sigmon Coal Company, Inc., et al., 2001 revolved around the interpretation and application of the Black Lung Benefits Act (BLBA). The BLBA was designed to provide benefits to coal miners who were totally disabled due to pneumoconiosis ("black lung disease"). In this case, a miner's widow sought survivor’s benefits after her husband died from a heart attack which she claimed was caused by his black lung disease. However, Sigmon Coal Company argued that they should not be held liable for these payments as there wasn't sufficient evidence linking the cause of death directly with black lung disease. The Supreme Court ruled in favor of Sigmon Coal Company stating that under the BLBA amendments made in 1981 and 1982, it is necessary for claimants seeking survivor’s benefits to prove that their spouse's death was due to pneumoconiosis or complications arising from it. This ruling clarified how causation must be established under the act and set an important precedent regarding liability for companies under such circumstances.

In the dissenting opinion for Barnhart v. Sigmon Coal Company, Inc., Justice Ginsburg argued that the majority's interpretation of the Black Lung Benefits Act was incorrect and unfair to coal miners. She believed that Congress intended for coal companies to be responsible for paying disability benefits to their employees who developed black lung disease as a result of their employment. The majority's decision, she argued, would unfairly shift this burden onto taxpayers by requiring the government to pay these benefits instead. Furthermore, she disagreed with the majority's view that a company could only be held liable if it employed a miner during his or her last year of work in a mine; rather, any company employing a miner at any point should share liability.