The opioid epidemic has been one of the biggest public health disasters in generations. The drug company at the heart of the crisis, Purdue Pharma, maker of the prescription painkiller OxyContin, agreed to a multibillion-dollar deal to settle thousands of claims against it — but that agreement would also grant the family behind the company, the Sacklers, immunity from additional civil lawsuits. Justices are now set to rule whether that settlement was legal. Abbie VanSickle, who covers the Supreme Court for The Times, explains what a decision either way could mean for the victims and for the people responsible.