The Globe and Mail reports from its Thursday, April 2, edition that a California jury's decision to hold Meta and Alphabet's YouTube liable for harms to a young woman's mental health has been greeted as a watershed moment. The Globe's guest columnist Michael Geist writes, however, that the legal theory the jury endorsed -- that social-media platforms are defectively designed products -- is the wrong tool for a real problem. Evidence at trial points to a genuine wrong, but it is not a design defect. These companies failed to take reasonable steps to mitigate risks. That is a duty-of-care problem, and it calls for a duty-of-care solution. Canada's proposed Online Harms Act offers a framework that might provide a solution. It does not treat platforms as defective products, nor does it resort to the blunt instrument of outright social-media bans for those under 16, measures that are easily circumvented, strip agency from both young users and their parents and ignore the genuine benefits many young people derive from on-line connection. Instead, the act would establish a regulatory structure in which platforms must assess risks and demonstrate they are taking reasonable measures to protect users from foreseeable harms.