Brown Prof Alleges Widespread AI Cheating on Exam

A Brown University economics professor says his experiment with a take-home exam backfired in a big way. Roberto Serrano suspects a majority of the 86 students in his "Welfare Economics and Social Choice Theory" course used AI tools to ace their midterm, producing unusually high scores—an average of 96% on what he says was a harder-than-usual test, per Inside Higher Ed. After comparing student responses with ChatGPT's, Serrano found the same oddly convoluted reasoning and atypical proof methods. He warned students that if in-person final exam scores didn't mirror the midterm's distribution, he'd toss the midterm grades.

They didn't. Eighteen students dropped the class, nine skipped the final, and the remaining students averaged 48.6%, a record low. According to a chart showing students' individual grades for both tests, only two students appeared to have not cheated. "I admire that person," Serrano says of one student who got a 55 on the midterm, then a slightly better 59 on the final, per Business Insider, noting that he'd hire that individual based on integrity alone. Serrano voided the midterm and made the final worth 80% of the course grade, per Inside Higher Ed; 19 students ended up ultimately failing the class.

Serrano says Brown's response—asking him to file individual cheating complaints and submit each exam—is impractical and overreliant on flawed AI-detection tools. The university counters it needs to wait for necessary documentation. The case lands as Brown releases a report urging clearer rules around generative AI, less emphasis on punishment, and recognition that AI use can't be perfectly policed.

Professors like Serrano, however, argue that institutions must treat AI-enabled cheating as an urgent threat to academic integrity. "We cannot afford to have a society in which a significant fraction of our best young minds think that cheating is OK," Serrano says. "That leads to a declining society, to a failed society ... We cannot choose to become idiots." He also says he'll no longer allow take-home exams, deeming what happened in his class a "wake-up call," per Business Insider.