He abused his position to engage in fraud for personal gain.
Tips
usage
弊 typically appears in compound words: 利弊 (pros and cons), 舞弊 (fraud), 作弊 (to cheat). As a standalone character it has a classical feel and is more common in written or formal Chinese.
memory
Think of 弊 as covering something up (廾 hands at the bottom, 敝 meaning worn-out on top) — something worn and hidden, like a fraud.
